In The Giver, what does the interaction between Jonas's parents reveal?

Jonas's parents are not like those who fall in love and decide to have children. They are assigned to live together like business partners for the sole purpose of rearing children to follow the rules of the community. After Jonas and his sister Lily are adults, his parents will not continue living together. Based on the information in the text, Jonas's parents are different from each other, because his mother works for the department of justice and seems to value rules and laws above anything else. On the other hand, Jonas's father is a Nurturer because he has the ability to take care of babies with great care and sensitivity.

Even though each parent is different, they work as a team to support both Lily and Jonas as they learn, grow, and develop in the community. They also don't disrespect one another in any way. Unfortunately, Jonas's parents do not understand or feel love. As a result, Jonas does not witness them holding hands, kissing, or showing affections towards one another. One scene that shows a good example of how his parents interact with each other is in chapter 16. Here, Jonas asks his parents if they love him and his father chuckles. He is then reminded of "precision of language" and his mother tells him the word is obsolete. Mother informs him that they "enjoy" him, though.

This conversation about love not only confirms that Jonas's parents are on the same team because they support and agree with one another, but it also proves that they are incapable of feeling deep emotions of love for their children or for each other.

Describe the relationship between Europeans, Native Americans, and Africans in the 1600's.

The relationship between Europeans, Africans and Indians was one that was dominated by Europeans. The primary reason for this dominance, of course, was the use of guns and superior weapons. Europeans also had the notion that their race was superior to African and Native races. They even used religion to justify their actions. In the New World, Europeans had already begun to settle by the 1600's. The Seventeenth Century was an important period for colonization in North America by Europeans. In 1629, the Puritans began arriving in New England. Their relationship with the Indians was one of cooperation, but it was also violent at times. Over time, the European populations that settled in America would remove Native Americans from their lands. This was done through unfair treaties, but most often by force. European diseases also ravaged the native populations.

The Seventeenth Century also marked an escalation of the European exploitation of Africans. The century saw the development of a large-scale trade network in which very few Africans benefited economically or politically. In 1619, the first slaves were brought to the territory that would become the United States. Millions of African slaves would be captured in Africa and brought to North America. Millions would die in the voyage. This dominant relationship was also based on superior weapons that the Europeans possessed. In the 1600's, Europeans like the Portuguese, Dutch, English and French perpetrated crimes against Indians and Africans that these groups would never recover from.

In Unwind, why doesn't Connor like the Admiral?

Connor doesn't like the Admiral because Connor, in general, has problems with authority figures.  

Connor is a rebellious teenager.  That is why his parents are having him unwound.  They simply don't know what to do about him any longer.  The Admiral is a major authority figure in the book.  He runs the Graveyard, which is a safe haven for runaway Unwinds.  The Admiral has lots of rules for the Unwinds that he is protecting.  An entire chapter is devoted to it in fact.  Additionally, the Admiral doesn't tolerate any Unwind slacking off.  They all must work.  Connor is not comfortable with that kind of authority over him.  

Connor also believes that the Admiral is using the Unwinds for his own gain.  

Work call infuriates Connor. He never puts his hand up, even if it's something he might actually want to do. "The Admiral's using us," he says to the kids around him. "Don't you see that?"

Most of the Unwinds do not agree with Connor or don't care.  In fact, Hayden tells Connor that he would rather be used whole instead of in pieces.  

Another reason for why Connor doesn't like the Admiral is because Connor doesn't trust him.  Connor doesn't trust the Admiral to have the Unwinds' best interest in mind, because Connor believes that the Admiral has body parts from an Unwind.  

"Pretty obvious that they're not his. I hear he keeps a picture of the kid he got them from in his office. An Unwind like us, who, thanks to him, never made it to eighteen. Makes you wonder how much more of him comes from us. Makes you wonder if there's anything left of the original Admiral at all."

Connor doesn't believe the Admiral truly wants to save Unwinds, because the Admiral has obviously benefited from the parts of an Unwind. 

How would you summarize "El Cuadro Mejor Vendido" by Gerardo Murillo?

This short story by Gerardo Murillo, whose artistic name is signed as "Dr. Atl," is about a talented artist who paints a vivid picture of the little town of Anáhuac. One of the inhabitants, a poor old lady who lived in a shack that the artist also captured, came over to ask whether she could look at the picture. 

She comments that the picture is more beautiful than the real passage. The artist offers to sell the painting to the lady. She is poor, so she cannot purchase it. He then offers to sell it to her for a mere 5 Mexican pesos.

The lady is shocked that the artist would be willing to sell it for so little, as the paint alone would have cost much more than that. The lady offers to keep the painting for a few days to just look at it, but the artist insists on selling it cheap. 

The lady takes the artist to her house, takes the five pesos in different coins out of a pot, and pays the artist. 

The artist feels very happy because the painting will be honored, and cherished more in the house of the old woman than in the most expensive gallery in the world. 

Another way to summarize the story, without the extra details, would be as follows:

An artist paints a vivid picture of a small town. An inhabitant admires the  picture, and the artist offers to sell the painting for five pesos. Even though it is a small amount of money, the artist prefers to sell it cheap to a true admirer of his art than to a gallery. 

"El Cuadro Mejor Vendido" translates into "The Best Selling Painting"; the title is ironic because the painting was sold for very cheap and to just one person. However, it would be the best sale the artist ever made, because he gave the painting to someone whose heart was as much in the painting as the artist's own heart was.

How do the branches of the government contribute to the process of a bill becoming a law?

The branches of government play a role in how a bill becomes a law. While the main part of the process belongs to the legislative branch, the executive branch and the judicial branch may play a role. It is possible for the President to suggest to Congress an idea for a bill. The Supreme Court, through previous rulings, may shed some light on what may or may not be acceptable in a possible bill.

The main part of the process belongs to Congress. A bill gets introduced into one of the houses of Congress. It will go to a committee, and if the committee recommends that the full house act on it, the full house will vote on the bill. Then, if it passes, it goes to the other house of Congress, and the same process occurs again. Once the bill passes both houses of Congress in identical form, it will go the President. The President may sign the bill into law, or the President may veto the bill. If it is vetoed, it goes back to Congress. If two-thirds of both houses of Congress vote to override the veto, the bill will become a law.

The judicial branch could be asked to review a law to determine if it is or isn’t constitutional. If the law was unconstitutional, the law would stop being in effect once the ruling was made. The Supreme Court has the final say on any law that is in the court system.

While most of the responsibility falls to the legislative branch, the executive and the judicial branches have some role in the lawmaking process.

Do you think Marlow's admiration and envy are justified in Joseph Conrad's Heart of Darkness?

Though Kurtz is clearly morally reprehensible (at least by the time we the readers meet him), there is a sense that Marlow's admiration and envy of the man is, in fact, justified. This justification has little to do with the terrible things Kurtz does; rather, it relies on the hypnotic and powerful things Kurtz says.

Conrad often describes Kurtz as a terribly powerful voice capable of exerting control over all who hear it. The sheer power of this voice, and by extension Kurtz himself, can clearly be seen in the way that all of the ivory traders in the company admire and envy Kurtz, even if they also fear him. Indeed, even the people who don't even seem to like Kurtz that much cannot help but fall under the man's spell, especially once he starts talking about all of his grand "plans." Thus, Conrad suggests Kurtz is something of a personified black hole; he pulls in all objects around him with a terrible and irresistible force. In that case, Marlow's envy and admiration would appear to be justified, as he seems to have almost no choice in the matter. Since Kurtz is incredibly charismatic, Marlow has little choice but to envy and admire the man. Indeed, toward the end of the novella, Marlow even seems to be disgusted by his own envy and admiration of Kurtz once he sees Kurtz's degradation. As such, it's possible for Marlow's envy and admiration of Kurtz to be justified, even though Kurtz is not an honorable man.  

For this assignment, I will have to write a screen play or script involving the topic of slavery. Please help me.

Slavery is an incredibly broad topic.  Assuming that your screenplay or script will be focused on slavery in America, you may want to select an aspect of it to focus on.

Slaves were brought to the New World from Africa for hundreds of years before the United States was even established as a country.  You may want to focus your script on the experiences of someone living in slavery.  

Native Africans were captured or sold by their own people to slave traders.  They had to endure terrifying and miserable journeys on slave ships in close quarters as they traveled across the Atlantic.  You could write about this aspect of slavery from the perspective of a Native African being taken from their home.  In this, you could contrast their life in Africa to their new future of being enslaved.

Slaves were bought and sold at slave auctions once they reached America.  This was a frightening process for slaves.  Many times families were split apart when one was sold to a different owner than the others.  Husbands and wives could be separated.  Children might be taken away from their mothers.  You could write about this horrifying time in your script, showing the dramatic emotions that slaves went through as they endured this terrible process.

Once slaves were purchased, they went to work for their owners.  Some worked on large plantations and in fields.  Others worked in homes.  If slaves tried to run away, they might be beaten.  You could write about the experiences of a slave and their working conditions.  You could also focus on how they settled into a new place with new people.

The Underground Railroad played an important role in the lives of some slaves.  The routes and the people along the way provided slaves a way to escape their difficult situations.  You could write about this suspenseful journey in your script.  Often, slaves who escaped were pursued by people or even dogs.  They had to hide in the woods or in the homes of "station masters" (people who helped slaves escape).  "Conductors" (such as the famous Harriet Tubman) helped to guide slaves on their journey.  Wanted posters offered rewards for their return to their master.

When writing your screenplay or script, you can show action through dialogue if you choose.  You may also want to add other details, such as differences in language.  A Native African would probably not speak English, and therefore would face the additional challenges of a language barrier.

I am attaching a few links, which contain a timeline, maps, and other helpful information on slavery.  Good luck!

What are twelve ways Robert Frost illustrates strong New England qualities in both character and setting in "The Housekeeper"?

Robert Frost's poem "The Housekeeper" calls on many New England themes and qualities; they are as follows:

1. The housekeeper is hardworking. She says "I can sew" (line 8), even though she is incapacitated in other ways.

2. The housekeeper disdains luxury. She says, "Lord, if were to dream of everyone / Who shoes I primped" (lines 13-14). She clearly has no use for luxuries herself.

3. The housekeeper is matter-of-fact about her need to move away from her home. She says, "Of course I can't stay here" (line 37).

4. The housekeeper, like many New Englanders, mourns the passing of time. "No one will ever live on it again," she says in line 53 about her old home.

5. The housekeeper advocates a stoic attitude. She says of John, the man of the house, "He's like a child" for letting family problems interfere with his life (line 58). She believes in going forward, no matter what her family's problems are.

6. The housekeeper believes in the redemptive power of nature. She says of John, "I thought the growing things would do him good" (line 63).

7. She's a tough character who has a gun (line 69) and isn't afraid of John or anyone else.

8. She believes in women's independence and the rightness of women leaving if they are mistreated (line 80). She says that if Estelle didn't want to live at the house, she was right to leave.

9. She's a freethinker and thinks it's all right to live with someone without being married (line 89-90).

10. She believes in women's rights and says that because her daughter has done the work on the farm, she's entitled to control the money (lines 116-117).

11. The housekeeper is a realist. She accepts that her daughter won't return (line 191-192).

12. She is observant. She knows when John is coming back home and what he'll say (line 213).

How does Shakespeare present the relationship of Macbeth and Lady Macbeth in the first two acts of Macbeth?

In the first two acts of the play, Shakespeare largely presents that Macbeths as equals within their relationship, companions who are very well matched and suited to one another.  When Macbeth writes a letter home to his wife, he calls her his "dearest partner of greatness" and says that he's written to her so that she "might'st not lose the dues of rejoicing by being ignorant of what greatness is promised thee" (1.5.11, 12-13).  Thus, he considers her to be his partner, his equal, something that would be fairly unusual during the era in which the play is set (the first half of the 11th century) or the era in which Shakespeare is writing (the first half of the 17th century).  Further, he cares a great deal about her feelings and her happiness, and he wouldn't want to deprive her of any reason to feel glad, as he's sure she will when she's learned of his new title and the Weird Sisters' prophecies.

Even after Macbeth has murdered Duncan, the Macbeths seem to complement one another.  When he panics, she remains calm.  When he is too afraid to return the daggers to the room, she is willing.  When he feels his conscience is too laden, now, with guilt, she assures him that "A little water clears [them] of this deed" (2.2.86).  Then, when Duncan's death is discovered, and Macbeth breaks from the plan and kills the chamberlains that he and Lady Macbeth were attempting to frame, others begin to look somewhat suspiciously upon Macbeth, questioning his actions.  Lady Macbeth distracts them by pretending to swoon, crying, "Help me hence, ho!" so that attention will be drawn away from him and on to her (2.3.138).  In all, the couple seems to work well together because they have a genuine care for one another and are relative equals within their relationship.

Why does Black Beauty get sick in Anna Sewell's story?

In Part 1, Chapter 19 of Anna Sewell's Black Beauty, soon after Little Joe Green replaces James Howard as the stable boy at Squire Gordon's Birtwick Hall, Mistress Gordon falls ill in the middle of the night. John Manly, the coachman, arouses Black Beauty, called Beauty for short, and rides him to fetch the doctor to save the mistress's life. Beauty rides with all his might and is soon safely returned to his stable. However, sadly, Joe, being new and ignorant, makes a terrible mistake with the care of Beauty that makes him ill, nearly to the point of death.

Not only does Beauty ride John to the doctor's, he also rides the doctor to Squire Gordon's. Upon Beauty's arrival back at Squire Gordon's, Beauty describes himself as having shaking legs, being able to do nothing but "stand and pant," and being completely soaked with sweat:

I had not a dry hair on my body, the water ran down my legs, and I steamed all over. (Ch. 19, Pt. 1)

Under the care of young Joe, whom Beauty is sure "did the very best he knew," Beauty was rubbed down, given nice cold water to drink, and fed hay and corn. But, thinking that Beauty was hot, Joe makes the terrible mistake of not covering Beauty up with his "warm cloth." Joe did not realize that, as a result of the sweat and cold water, Beauty would soon be freezing cold.

Left alone in his box in the stable, Beauty grows so freezing cold that he trembles, aches, and feels "sore all over." When John finally enters the stable that night, he finds Beauty lying down in his hay and moaning with pain. John quickly covers him up with multiple blankets and makes him warm gruel to drink. But the damage was already done; the next morning, Beauty has a lung infection so bad he "could not draw [his] breath without pain." But, luckily, with medicine and daily veterinary care, Beauty returns to health.

What items would Jem finch put in a time capsule and how do they represent him?

There are a variety of items that Jem would put into a time capsule to represent himself. The first item is the boy soap doll that Boo Radley leaves for Jem in the tree. This doll is one of the first acts of kindness that Boo shows Jem and his sister, Scout. It also signifies the beginning of the relationship between Boo and the two Finch children.

The second item is the arm cast that Jem wears at the end of the novel. When Bob Ewell attempts to kill Jem and Scout, Jem's left arm breaks during the fight. The cast not only represents his brush with death, but also the debt he owes to Boo Radley for saving his and Scout's life. Also, the cast represents why Jem's left arm will always be a little shorter than his right arm. 

The final item Jem might put inside a time capsule is the small piece of the Radley house he touches to show Scout and Dill that he is brave. Being a brave older brother is very important to Jem, and this item represents a time when he was able to impress his younger sister.

What do you learn about Prince Prospero from his desire and his attempts to keep his household free of the plague in "The Masque of the Red Death"...

Prince Prospero is selfish and cares more about the wealthy members of his kingdom than the general public. 

The fact that Prospero builds himself a castle and holes himself up inside of it with the wealthy constituents of his kingdom shows he has no interest in actually taking care of his people. He does not try to stop the plague or protect his kingdom from its devastating social and economic effects. He just flees. 

When his dominions were half depopulated, he summoned to his presence a thousand hale and light-hearted friends from among the knights and dames of his court, and with these retired to the deep seclusion of one of his castellated abbeys. This was an extensive and magnificent structure, the creation of the prince's own eccentric yet august taste. 

The act of walling himself up inside the abbey and throwing a big party also shows Prospero is delusional. First of all, it is ridiculous to think they will be safe just because no one can get in or leave. Second, throwing a party is a terrible waste of resources when your people are dying. Prospero is in denial. 

Prospero’s decorating style is creepy and bizarre. The scariest part is the ebony clock, which chimes to seem like death itself. The revelers stop when they hear it.

But, in spite of these things, it was a gay and magnificent revel. The tastes of the duke were peculiar. He had a fine eye for colors and effects. He disregarded the decora of mere fashion. His plans were bold and fiery, and his conceptions glowed with barbaric lustre.

It turns out that you can't actually just build a spectacular abbey and escape death. Death finds Prospero anyway. He crashes the party in physical form. Prospero's selfishness catches up with him and his guests.

What are some good examples of thesis statements for an essay based on Robert Frost's poem "The Road Not Taken"?

Here's one possible thesis statement: Frost shows, in his poem "The Road Not Taken," that there is no road less traveled, that it is ultimately impossible to make a totally unique choice, because others have always made each choice available to us many times before.  He says that the second road is "just as fair" as the first, though it is somewhat grassier.  However, "as for that the passing there / Had worn them really about the same."  In other words, about the same number of people have taken each of these roads and so they are equally worn, even if they are different in appearance.  Further, both of them "that morning equally lay," and so his choice of which road to take, i.e. which choice to make in the symbolism of the poem, is relatively arbitrary and based on little else besides first impression.

Another possible thesis: The speaker in Robert Frost's "The Road Not Taken" plans to lie later on in his life, telling people that he took the road that fewer people had taken, because all humans want to believe that they make unique choices that have significant impact on our lives; however, the poem shows that such choices are ultimately unavailable to us.  To defend this thesis, you can rely on much the same evidence as above.  However, the narrator's plan to tell people that the road he chose, i.e. the decision he made, "made all the difference" in his life, explains why he will tell this story "with a sigh."  It is a falsehood, and whether he tells it for his own sake or his auditors' is unclear.  Perhaps it is for both, because it seems like human nature to feel that we've made important decisions that really have made a difference in the courses our lives take, although the poem does not support this as a possible reality.

What's the answer to life, the universe, and everything?

The answer to the great Question of Life, the Universe, and Everything is . . . 42. 

That's the answer that Deep Thought gives at the end of chapter 27.  Phouchg and Loonquawl are obviously mystified and even a bit upset.  They can't believe that the answer to the ultimate question is a seemingly random number. 

”Forty-two!” yelled Loonquawl. ”Is that all you’ve got to show for seven and a half million years’ work?”

Deep Thought confirms that, yes, 42 is definitely the correct answer, but Deep Thought admits that he thinks the problem is that the initial question is incorrect.  

"I think the problem, to be quite honest with you, is that you’ve never actually known what the question is. . . So once you do know what the question actually is, you’ll know what the answer means.”

So Deep Thought builds a "machine" to answer the question of what is the actual real question.  He calls his machine "Earth."  Unfortunately with only 5 minutes to go before Earth reveals the question, the Vogons showed up and destroyed the planet.  Earth Two begins, and to make a confusing story more frustrating, the answer is still 42, but the question is still unknown.  Book ends. 

In Freak the Mighty, what does the cop say that alludes to the fact that Max's dad is in prison?

In chapter seven, Max and Kevin join forces to escape the attack of Tony D. and his gang. With Kevin on Max's shoulders, Kevin does the thinking and directing while Max does the running. They end up running into the pond to get away from Tony's blade, but then the bullies start throwing rocks at the boys. Fortunately, Kevin can whistle loud enough to attract the attention of a cop car. The cop car shines a bright spotlight over the pond and discovers the boys. Eventually, the cops get ropes to assist in recovering the boys from the pond. The boys are given blankets and Cokes while also being told that they will keep an eye out for Tony D.--not to worry. Then, one of the cops asks for the boys' names so they can start calling mothers. When Maxwell tells them his name, one cop says the following:

"Hey, isn't that Kenny Kane's boy? Must be. Old Killer Kane, is he still inside?" (39).

There are two things that the cop says that help a reader infer that Killer Kane is in prison. First, the reference to the name "Killer Kane" references what Max's dad is accused of doing--killing someone. Then, the cops says "still inside," which can be inferred as meaning that Kane is still in prison. At this point in the book, the readers don't know much about Max's parents other than the fact that his mother had died. What the cop says not only gives information into the status of Max's father, but it is also a little bit of a foreshadowing that Killer Kane will be in the story at a future time. If Kane were not to be mentioned further in the story, then there wouldn't be much reason to mention him now; so, the reader's mind is primed for future events surrounding Killer Kane.

Compare and contrast the French Revolution (1789) and the Russian Revolution (1917). How did leaders use nationalism and propaganda to gain...

The French and Russian revolutions both had multiple causes, economic, social and ideological. Although they were separated in time by over a century, they actually occurred in relatively similar internal developmental contexts, as Russia in the early twentieth century was still an agrarian economy led by a monarch, unlike western Europe which underwent the industrial revolution in the late eighteenth and nineteenth centuries. 

In both countries, similar economic factors contributed to the revolutionary impulse. First, there was a dramatic degree of economic inequality. The was exacerbated by the way wealthy monarchs and nobles created extravagant displays of their wealth. Second, both countries were heavily indebted and their monarchs kept increasing taxation to sustain their own extravagant lifestyles. Third, both some of the French peasants and the Russian bourgeois were beginning to acquire some wealth engendering what Marx called a "revolution of rising expectations." Socially, the upper classes had many freedoms and acted with impunity while the lower classes were restricted from roles of power and a voice in running their country, breeding resentment. 

In both cases, ideology played a role in the revolutions, but while the ideology behind the French one was Enlightenment liberalism, that behind the French one was Marxist, and valued the collective over the individual. Both revolutions were strongly anti-clerical and anti-religious. The Russian Revolution, though, was the more radical of the two, addressing gender and class in a more critical fashion. 

Finally, in both revolutions, the original collectivism and ideological purity succumbed to the attractions of charismatic leaders, who used forces of propaganda and nationalism to create authoritarian states.

What did Helen mean when she said, "Knowledge is love and light and vision" in The Story of My Life?

As a young girl, Helen Keller became deaf and blind due to an illness. Her life was plunged into darkness. Her parents were determined to seek help for her. They wanted Helen to get an education and to learn how to communicate. They sought expert after expert to find help. They were eventually told to contact Mr. Anagnos, who ran a school for the blind. It was through him that they found Annie Sullivan, the woman who became Helen's teacher. Miss Sullivan helped lift Helen from the darkness she had lived in for years. Helen looked back on this and described it using a metaphor:

Thus I came up out of Egypt and stood before Sinai, and a power divine touched my spirit and gave it sight, so that I beheld many wonders. And from the sacred mountain I heard a voice which said, "Knowledge is love and light and vision."

Helen compared her emergence from darkness to the Hebrew people escaping from Egypt. She also referred to Moses, who encountered God on Mount Sinai. She metaphorically heard a voice speaking to her. Through knowledge, Helen discovered "love and light and vision."

Why is gymnastics difficult?

Gymnastics can be difficult both as a hobby and a profession because it requires a person to set aside a lot of time for practice. Additionally, a person should be in good health to be able to keep up with the demanding physical activity gymnastics involves. Most people to practice gymnastics as a hobby or profession begin their training from a very young age. This is both to get an early start on learning technique as well as to begin developing the muscle strength and flexibility necessary to perform. If an adult tries to begin performing gymnastics without any prior experience, they would likely find it very difficult because they haven't grown up learning to perform the kinds of activities gymnasts do. What's more, a person's flexibility generally decreases as they age, and this applies to both gymnasts and people who do not practice it. Many gymnasts grow out of their practice, either because their physical shape is not conducive to the activity, or because of bodily aches and pains.

As with any skill, gymnastics takes a lot of practice to even be able to perform the intricate leaps and twirls, let alone do them with any finesse. The profession of gymnastics is also highly competitive because there is such a small market for the kinds of abilities gymnasts have, but quite a lot of people grow up taking gymnastics lessons for physical fitness. Gymnastics is not only physically demanding, but requires the gymnast to do a lot of real-time calculations, spatial awareness processing, and memorization in order to pull off a performance.

In Harper Lee's To Kill a Mockingbird, what does Miss Maudie mean when she says that "sometimes the Bible in the hands of one man is worse than a...

To understand what Miss Maudie means, let's look at the context of their conversation.

Scout and Jem are talking with her, a lady whom Scout describes as a trusted, intelligent adult:

"Jem and I had considerable faith in Miss Maudie. She had never told on us, had never played cat-and-mouse with us, she was not at all interested in our private lives. She was our friend."

The kids are trying to understand why Boo always stays inside his house, and Miss Maudie is trying to explain. She starts by mentioning that Boo's father was "a foot-washing Baptist," meaning someone who's so religious that they take everything from the Bible as literally true, and they think anything fun at all is a sin--like planting flowers instead of sitting inside to read the Bible. They even think women are sinful just because they're women.

That's when Miss Maudie delivers the line about the Bible being something destructive when one person uses it--more destructive than alcohol when someone else drinks it.

What she means is that some people use the Bible not as a way to gain wisdom and understanding, but as a weapon to restrict people's lives and demand that they act a certain way. Miss Maudie seems to be hinting that Boo's father was that zealous about his religion, and as a result he was so demanding about the things Boo could and couldn't do, that Boo felt immobilized (frozen) and suffered some kind of mental damage that resulted in him staying inside his house all the time.

Miss Maudie was trying to be clear when she said that the Bible was worse when one man wields it compared to if Atticus were to drink alcohol--she was trying to explain that religion, improperly interpreted and forced on someone, can be worse than if someone just gets drunk and treats people terribly or violently. But the kids don't really understand the comparison; they get stuck on thinking about how their father doesn't actually drink.

What are species-specific defense reactions?

Introduction

All living organisms live within complicated food and energy webs in which energy is transferred from organism to organism through consumption. Plants convert energy from sunlight to manufacture organic nutrients. Herbivorous animals eat plants to obtain this energy, and carnivorous animals eat herbivores and other carnivores to obtain the same energy. Within an animal species, individuals compete with one another for available food and natural resources to survive; in the process, they establish dominance hierarchies in which dominant individuals overpower subordinates. Among different species, interactions occur that lead to predation (an interspecific interaction in which the individuals of one animal species hunt and kill members of another species for food), disease, and parasitism; in each case, one species is feeding on another species.

Intraspecific competition and interspecific predation and parasitism represent principal animal behaviors important to the evolution of life. Each species possesses an innate (instinctive) drive to survive and to continue the transmission of its deoxyribonucleic acid (DNA) in space and time. Within the food webs of the living environment, each species evolves specific adaptations for survival that enable it to carve out a particular habitat, or place to live, and niche, or occupation, in the environment. Because the food webs of life on Earth are circular, the evolution of competition and predation are necessary for life to continue. All species will become predators (hunters) of certain other species and will simultaneously be prey (the hunted) for certain different species.

Learned and Genetic Adaptations

To survive, each species possesses specific adaptations for hunting its prey and for defending itself from predators. Defensive mechanisms come in many different varieties. Some very effective defense mechanisms are highly conserved between different species; other defenses are unique to only one or a few species. Of these defenses, some are instinctive, occurring automatically because of biochemical changes within individual animals, whereas others are learned from environmental experiences. Learned defensive mechanisms are prevalent in highly social mammal and bird species.

Intraspecific competition occurs among individuals of a given population or group and among different populations or groups. Within a population, the social structure is either genetically or behaviorally conditioned to construct castes ordominance hierarchies in which dominant individuals are superior to more subordinate individuals. The social insects (such as ants, termites, bees, and wasps), whose behavior is almost exclusively genetic in nature, construct their societies, or hives, around castes that have specific jobs to perform. Such societies revolve around a central fertile queen, sterile female workers, and male drones. Workers are subdivided into several specializations, such as hunting for food and defending the hive. Soldier workers have specialized body structures for attacking intruders; furthermore, they release pheromones (hormonal attractants) from their bodies at the sign of danger to attract other soldier workers to the region of intrusion.

Dominance Hierarchies

Within the highly social and intelligent mammal and bird species, populations either migrate in bands or groups or set up individual adjacent territories that are heavily defended by the owner. In either of these situations, learned dominance hierarchies are established in which stronger individuals outcompete weaker individuals, thereby establishing a “pecking order” (as it is called for chickens) of precisely ranked dominant individuals to progressively more subordinate individuals. The dominant individuals possess the best territory, the most food, and the most mates. The most dominant individuals also have the best protection from predators, because their territories are central and therefore are shielded by the territories of more subordinate individuals. Consequently, the most subordinate individuals have the worst territories, poor food, few if any mates, and poor protection from predators, which usually attack outskirt territories. These territories are maintained by constant fighting among males, especially during the breeding season. Males vocalize and present visual displays (visual dances or series of movements or gestures by individuals to communicate such things as dominance, aggression, and courtship to other individuals) to force their opponents to submit; submission is routine, and few encounters are fatal.

Predator-Prey Interactions

In interspecific predator-prey interactions, the prey utilize a variety of quick-response defenses. One of the most common defenses is the flocking or herding defense. When a predator approaches a group of prey and is identified, the discovering prey individual announces danger by a vocalization (an alarm call), specific movement, or the release of chemical pheromones to warn the other members of the group. The prey group response is instantaneous, with all members contracting into a dense mass. A predator is less likely to succeed in capturing a prey individual during an attack on a compact group than when the prey individuals are scattered. Furthermore, the predator may sustain personal physical damage in an attack on a compact group, which easily could turn on the predator. Most predators are far more successful at capturing very young, old, or sickly individuals that are isolated or located at the poorly defended outskirts of a prey group. Some predators, such as hawks, falcons, and wolves, do make repeated passes at compact groups in sometimes successful attempts at panicking individuals and thereby scattering the group. Flocking behavior is a very effective defense that is utilized by bees, fish, tadpoles, most bird species, and most mammal species. Prey species usually utilize excellent vision, hearing, and sense of smell.

The dynamics of predator-prey interactions can be complicated, although numerous mathematical models of such relationships have been developed that enable researchers to make predictions concerning future interactions in natural populations. Predator-prey interactions are important for the stability and survival of both predator and prey populations. Without prey, predators would die; however, without predators, prey populations would grow unchecked until they exceeded the available resources in the environment, ending in a massive population crash in which many individuals would die. Such occurrences have been thoroughly documented in many species, including moose, deer, rabbit, and even human populations. Defensive mechanisms are important to all species to ensure the survival of enough members of each species population to reproduce and continue the transmission of the species’ genetic information. Perfect defense, however, could be as detrimental to the population as no defense. Numerous mathematical ecologists have developed impressive models of animal population growth based on predator-prey interactions. Among the most famous models are those that were developed by Alfred Lotka and Vito Volterra, and they still are in use. Such models are of critical importance to the study of human overpopulation.

Animal Defense Mechanisms

Other species-specific defense mechanisms include camouflage, mimicry (an inherited or behavioral defense phenomenon in which an individual of a species either looks dangerous to its predators or can exaggerate its appearance to fool a predator), predator saturation (a defensive mechanism in some animal species in which a prey animal population synchronizes its growth so that it becomes too large for predators to consume any significant fraction of the population), and long-term incubation. Most species have adaptations in skin and fur coloration to blend in with their particular environment. For example, albino hares and squirrels predominate in areas that have snow for a good portion of the year, whereas the same species in more temperate climates usually have a grayish-brown coloration. Zebras have a striped pattern that enables them to blend with tall grass; many mammalian predators (lions, wild dogs) are color blind. Some species (the chameleon, for example) can alter their body color to their background through biochemical changes in their skin. Some lizard species simply discard body parts, such as their tails, when captured by predators.

Müllerian mimicry is a phenomenon used by moths and butterflies to defend themselves from bird predators. A few butterfly species with bright orange-black wings are poisonous; several dozen nonpoisonous species have coevolved bright black and orange or yellow wings and are therefore less likely to be eaten, since birds learn avoidance very quickly from only a few encounters with the poisonous varieties. Some species of fish, birds, and mammals have short, rapid bursts of reproduction, so that their predators are overwhelmed, or saturated, by the high prey densities. In both of these instances, some prey are eaten. The thirteen- and seventeen-year periodic locust species of North America combat predation by burrowing underground for many years before surfacing and reproducing within only a few weeks.

Implications for Human Society

The study of species-specific defensive reactions is of intense interest to animal behavior researchers. Research into such behavior enables them to understand how highly adaptive and elaborate defenses have evolved in animal species over the past five hundred million years. These studies also have potential impact on the psychology of human behavior. Humans are very territorial animals and exhibit considerable competitive behavior, including interpersonal conflicts and aggression. Consequently, defense mechanism studies are strongly applicable to the study of human conflict, social tensions, and warfare. Furthermore, species-specific defense mechanisms are also of interest to medicine, since humans, while being the apparently dominant species on Earth, are subject to predation, particularly from parasitic bacterial, fungal, and viral diseases.

The explosion of human technological growth during the past century has included medical advances that have eradicated many diseases that once were major killers of humans. Medicine has been a tremendous artificial defense mechanism developed by the intelligence of the human species. It has defeated dozens of bacterial, fungal, and viral predators and parasites of humans. Because of these advances, humans live longer and better lives, human birthrates have soared, and human death rates have declined; however, the elimination of human predators has produced some serious problems. One is overpopulation. The explosive human population growth is approaching the planet’s carrying capacity (the available food and resources). Some areas of the world, most notably Asia and Africa, have already seen human overpopulation far above the carrying capacity; the result has been devastating famines and millions of deaths. Furthermore, medical science is taxed by the appearance of new mutated viral and bacterial predators to replace the eradicated ones. The human immunodeficiency virus (HIV), which causes acquired immunodeficiency syndrome (AIDS), is an example. Furthermore, certain diseases, such as cholera, are on the rise worldwide. Life on Earth is very homeostatic (self-regulatory); it contains mechanisms for keeping populations of all species in check.

Leaving the microscopic scale, humans and other primates defend themselves from competitors and very large predators in much the same fashion. Humans have territories that each territory-holder defends. Furthermore, several dominant males may group to attack intruders and other predators. There can be no doubt that such behavior has evolved into the large armies that different countries have amassed to defend their territorial borders. The structure of many such armies is somewhat reminiscent of mammalian dominance hierarchies. The frontline soldiers who face the brunt of an opponent’s attack usually are individuals who are less equipped and trained. They are sometimes called “cannon fodder.” Better-trained, more dominant individuals follow; they are more likely to survive hostile encounters with the enemy.

Species-specific defensive behaviors are also applicable to human behavior in terms of social and personal relationships. Complex human societies are rigidly structured along territorial lines, with laws to regulate the behaviors of individuals. Cross sections through American cities reveal the segregation of the poor from the middle class from the rich, and the segregation of black from white from Hispanic. Individuals in each of these groups construct physical, social, and legal barriers to defend themselves from competition from outsiders. With overpopulation and competition for resources, individuals and countries resort to mechanical weapons ranging from handguns to semiautomatic rifles to atomic bombs. Stress, inequality, and mistrust of others involve biological reactions that have evolved over hundreds of millions of years.

Each animal species on Earth has evolved through the endurance of predator-prey interactions. Understanding how species defend themselves can be of great importance in helping endangered species to survive and in controlling the overpopulations of species and the spread of disease. It also can help humankind to alleviate many of its own species’ social problems.

Understanding Ecosystems

The study of species-specific defense mechanisms is of considerable interest to animal behaviorists and psychologists because of their implications for human behavior. All animal behaviors can be influenced by endogenous (instinctive) or exogenous (environmental) factors. Endogenous behaviors
include imprinting and biochemical changes within the body of the individual that enable one to recognize events or situations instantaneously for survival. Behaviors such as recognizing danger are critical for survival and therefore must be instinctive. Within the intelligent and highly social mammals and birds, a period of learning during infancy enables the development of exogenous behaviors from experiences in one’s immediate environment. Such learned behaviors are of equal importance in such species.

The study of species-specific defensive reactions allows scientists to uncover the intricacies of species interactions within the environment. In any given ecosystem (such as a forest, grassland, ocean, or desert), populations of thousands of different species are linked by intricate food webs. The destruction of the environment or the extinction of any one species can have irreparable effects on all the other species within the ecosystem. The defensive mechanisms of most species can work only so well.

Bibliography

Andrewartha, Herbert George. Introduction to the Study of Animal Populations. 2d ed. Chicago: U of Chicago P, 1971. Print.

Choi, Charles Q. "Bug vs. Superbug." Scientific American 309.2 (2013): 24. Print.

Forbes, Peter. "Masters of Disguise." Scientific American 304.5 (2011): 80–83. Print.

Klopfer, Peter H., and Jack P. Hailman. An Introduction to Animal Behavior: Ethology’s First Century. 2d ed. Englewood Cliffs: Prentice-Hall, 1974. Print.

Krebs, Charles J. Ecology: The Experimental Analysis of Distribution and Abundance. 5th ed. Reading: Addison, 2000. Print.

Lorenz, Konrad. On Aggression. Translated by Marjorie Kerr Wilson. New York: Routledge, 2002. Print.

Manning, Aubrey, and Marian Stamp Dawkins. An Introduction to Animal Behavior. 5th ed. New York: Cambridge UP, 2006. Print.

Marras, Stefano. "Schooling Fish Under Attack Are Not All Equal: Some Lead, Others Follow." PLoS ONE 8.6 (2013): 1–7. Print.

Wilson, Edward O. Sociobiology: The New Synthesis. 1975. 25th anniversary ed. Cambridge, Mass.: Belknap Press of Harvard UP, 2000. Print

Who else has detained Odysseus besides Calypso in The Odyssey?

The goddess Circe also holds Odysseus captive.

After Calypso releases Odysseus, he has a number of misadventures, one of which was with the Cyclops. However, he is eventually able to trick the Cyclops and blind him. As he and his men depart, Odysseus has the audacity to taunt the Cyclops. Unfortunately for Odysseus, the Cyclops is the son of Poseidon, who then takes revenge upon Odysseus. 

After more difficulties, Odysseus lands on the island of the god of wind, Aeolus, who seals the world's winds in a bag except for the one to take Odysseus home. But, as he sleeps, some of his seamen think there is treasure in the bag and open it. With all the winds released, new disasters occur and the fleet is lost except for the ship of Odysseus which manages to escape alone. This ship arrives on the island of Circe, "a great and cunning goddess."

Presently they reached the gates of the goddess' house, and as they stood there they could hear Circe within, singing most beautifully as she worked at her loom, making a web so fine, so soft, and of such dazzling colors as no one but a goddess could weave.

Then, Circe comes to the doorway and beckons them inside. On the enchantress Circe's invitation, the men enter, but Odysseus stays on the ship and Eurylochus refuses to pass through the doorway with the crew, suspecting "mischief." Unfortunately for these men, they are changed into swine.
When Odysseus learns what has happened, he rushes to the cottage of Circe despite warnings from Eurylochus. Fortuitously, Hermes appears to Odysseus and provides him with an herb to wear around his neck which will protect him from the spells of Circe. Hermes also instructs Odysseus how to overpower Circe and save himself and his men. As it turns out, Circe casts off the spell on the crew and Odysseus and his men remain on her island for a year. Finally, Eurylochus convinces Odysseus that they must resume their efforts to return home. Circe keeps her vow to assist them, but she instructs them to consult with the spirit of the blind prophet Tiresias in the Land of the Dead before sailing for Ithaca. With her instructions and provisions, the Greeks set sail.

 

Is NH4+ an electrophile?

An electrophile is a species that can accommodate additional electrons. Let us look at the structure of the ammonium ion (NH4+). Nitrogen has an atomic number of 7 and an electronic configuration of 1s2, 2s2, 2p3. In an ammonium ion, nitrogen is bonded to hydrogen atoms and shares electrons with them. This causes all the orbitals to be fully filled and hence, nitrogen does not have space for any additional electrons. Thus, the ammonium ion is not an electrophile. 

Having said that, ammonium still participates in reactions. What really happens is that the ammonium ion gets rid of the proton (H+) to achieve more stability. It is this hydrogen ion that seeks electrons and gains them during bonding with other species. Hence the hydrogen ion is the electrophile, not the ammonium ion. 

Take a look at this reaction:

`NH_4^+ + OH^(-) -> NH_3 + H_2O`

Hope this helps.

What colors or elements of nature does the Friar discuss in his monologue?

Friar Lawrence delivers a monologue (a speech that he says aloud to just himself -- so, really, a speech given directly to the audience) in Act II, Scene 3, before Romeo walks in. The Friar talks a little more, finishing up his monologue, and then greets Romeo. This whole monologue is about nature, especially the power of natural herbs to heal and hurt the body.

He starts by talking about the clouds, the sun and its morning light, and the dew, as well as the disappearing night:

"The gray-eyed morn smiles on the frowning night,

Checkering the eastern clouds with streaks of light,

And fleckled darkness like a drunkard reels

From forth day’s path and Titan’s fiery wheels.

Now, ere the sun advance his burning eye,

The day to cheer and night’s dank dew to dry,"

Then he talks about filling up the basket he's carrying with both poisonous weeds and healing flowers:

"I must upfill this osier cage of ours

With baleful weeds and precious-juicèd flowers."

Next, he compares the earth to a grave and a mother's womb. He talks more about the herbs that come out of the earth, which, like children, are both useful and diverse:

"The earth, that’s nature’s mother, is her tomb.

What is her burying, grave that is her womb.

And from her womb children of divers kind

We sucking on her natural bosom find,

Many for many virtues excellent,

None but for some and yet all different."

He mentions the power and grace of "herbs, plants, [and] stones," and then says that any herb growing in the earth that seems poisonous also has some good quality, but that helpful herbs can also be used for harm:

"For naught so vile that on the earth doth live

But to the earth some special good doth give.

Nor aught so good but, strained from that fair use

Revolts from true birth, stumbling on abuse."

After Romeo comes in, as if finishing his thoughts, the Friar gives an example of a plant with both good and bad qualities. He talks about a particular flower he's holding, saying it can either be poison or medicine depending on whether you smell it or taste it:

"Within the infant rind of this small flower

Poison hath residence and medicine power.

For this, being smelt, with that part cheers each part;

Being tasted, stays all senses with the heart."

Although the Friar mentions many descriptions of shade and light (such as darkness and murkiness), the only color he directly mentions is gray:

"The gray-eyed morn smiles on the frowning night"

That's how the Friar starts his monologue. What he's really saying is that the sun is rising because it's early morning, but he's expressing that thought by imagining that the morning, which has gray eyes, is smiling at the night, which frowns.

Mentioning that the morning has gray eyes focused on the outgoing nighttime, and observing "streaks of light" and "fleckled darkness" helps the Friar express the dual, competing elements of nature, which is appropriate considering how he keeps coming back to the idea that all herbs (and people) have both good and bad inside them.

All of this figurative speech about nature -- especially the reverence with which he shows the natural world -- helps to characterize the Friar as an unusually insightful character, deeply connected to the earth, and knowledgeable about ways to heal and poison people. 

What are the weekend preparations needed for a party to take place at Gatsby's mansion?

Nick describes the ambitious and elaborate preparations for Gatsby's parties in chapter three. Caterers come and set up enormous canvas tents and a dance floor and decorate with colored lights and flowers. Oranges and lemons arrive by the crate and are juiced by Gatsby's butler. Buffet tables are generously filled with food, and Gatsby has a fully stocked bar set up even though Prohibition is in effect. He hires a full orchestra, and performers from New York come to entertain. Waiters are brought in to serve his guests. Gatsby employs gardeners and handymen to prepare his lawn and gardens and then clean and repair damage after the parties. He sends a station wagon to pick up guests at the train station, and some arrive chauffeured by Gatsby's Rolls Royce. He has two motorboats and a seaplane and a raft with a tower for swimmers on his beachfront.

Fitzgerald, F. Scott. The Great Gatsby. Charles Scribner's Sons, 1925.

Which quotes about deception can one find in the first and second scenes of Macbeth?

In scene 1, we encounter the witches who are planning to meet Macbeth on the heath later, before sunset, when all the fighting is over. In the last lines of the scene, they say the following:

Fair is foul, and foul is fair:
Hover through the fog and filthy air.

This seeming contradiction is an obvious indication of their purpose later. Their reference to 'foul' suggests something disgusting or evil, whilst 'fair' suggests goodness and something wholesome. They equate the two—the one is the other. They intend using deception to lead Macbeth into committing vile deeds whilst he believes they are good in the sense that he will benefit from them. Their deliberate use of such equivocal statements is what will eventually lead him to his doom.

In scene 2, King Duncan refers to the traitorous thane of Cawdor after his defeat and eventual arrest:

No more that thane of Cawdor shall deceive
Our bosom interest: go pronounce his present death,
And with his former title greet Macbeth.

The thane has deceived his king by probably feigning loyalty but actually plotting against him by assisting the traitor, Macdonwald, and Sweno, the Norwegian king. Duncan declares that Cawdor will nevermore have an opportunity to mislead him and thus thwart what is good for him, his countrymen, and the country itself. Now that he and the other two have been vanquished, to a great extent because of Macbeth's relentless pursuit and his courage, the king commands that he be executed and his title bestowed on Macbeth.

It is ironic that Duncan awards the traitor's title to Macbeth because it is this honour which actually provides Macbeth with an incentive to undertake his road to ruin. Furthermore, Cawdor's deception and betrayal foreshadow Macbeth's similar acts later, only with much more devastating outcomes.

What are natural treatments for osteoarthritis?

Introduction

In osteoarthritis, the cartilage in joints has become damaged,
disrupting the smooth gliding motion of the joint surfaces. The result is pain,
swelling, and deformity. The pain of osteoarthritis typically increases with joint
use and improves at rest. Although X rays can find evidence of arthritis, the
level of pain and stiffness experienced by people does not match the extent of
injury noticed on X rays.

Many theories exist about the causes of osteoarthritis, but no one really knows
what causes the disease. Osteoarthritis is often described as wear-and-tear
arthritis, but evidence suggests that this simple explanation is not correct. For
example, osteoarthritis frequently develops in many joints at the same time, often
symmetrically on both sides of the body, even when there is no reason to believe
that equal amounts of wear and tear are present. Another intriguing finding is
that osteoarthritis of the knee is commonly (and mysteriously) associated with
osteoarthritis of the hand. These factors, and others, have led to the suggestion
that osteoarthritis may actually be a body-wide disease of the cartilage.

During one’s lifetime, cartilage is constantly being turned
over by a balance of forces that both break down and rebuild it. One prevailing
theory suggests that osteoarthritis may represent a situation in which the
degrading forces become chaotic. Some of the proposed natural treatments for
osteoarthritis described here may inhibit enzymes that damage cartilage.

When the cartilage damage in osteoarthritis begins, the body responds by building
new cartilage. For several years, this compensating effort can keep the joint
functioning well. Some natural treatments appear to work by assisting the body in
repairing cartilage. Eventually, however, building forces cannot keep up with
destructive ones, and what develops is end-stage osteoarthritis. This is the
familiar picture of pain and impaired joint function.

The conventional medical treatment for osteoarthritis consists mainly of
anti-inflammatory drugs, such as naproxen and Celebrex. The
main problem with anti-inflammatory drugs is that they can cause ulcers.
Another possible problem is that they may actually speed the progression of
osteoarthritis by interfering with cartilage repair and by promoting cartilage
destruction. In contrast, two of the treatments described here might actually slow
the course of the disease, although this has not been proven.

Principal Proposed Natural Treatments

Several natural treatments for osteoarthritis have a meaningful, though not definitive, body of supporting evidence indicating that they can reduce pain and improve function. In addition, there is some evidence that glucosamine and chondroitin might offer the additional benefit of helping to prevent progressive joint damage.

Glucosamine. Inconsistent evidence hints that glucosamine
can reduce symptoms of mild to moderate arthritis; a small amount of evidence
indicates that regular use can slow down the gradual worsening of arthritis that
normally occurs with time.

Glucosamine appears to stimulate cartilage cells in the joints to make proteoglycans and collagen, two proteins essential for the proper function of joints. Glucosamine may also help prevent collagen from breaking down.

Glucosamine is widely accepted as a treatment for osteoarthritis. However, the supporting evidence that it works is somewhat inconsistent, with several of the most recent studies failing to find benefit. Two types of studies have been performed: those that compared glucosamine with placebo and those that compared it with standard medications.

In the placebo-controlled category, one of the best trials was a three-year double-blind study of 212 people with osteoarthritis of the knee. Participants receiving glucosamine showed reduced symptoms compared to those receiving placebo. Benefits were also seen in other double-blind, placebo-controlled studies, enrolling more than eight hundred people and ranging in length from four weeks to three years. Even more double-blind studies enrolling more than four hundred people compared glucosamine with ibuprofen and found glucosamine just as effective as the drug.

Most recent studies, however, have not shown benefit. In four studies involving
almost five hundred people, the use of glucosamine failed to improve symptoms to
any greater extent than placebo. In a study involving 222 participants with hip
osteoarthritis, two years of treatment with glucosamine was no better than placebo
at improving pain or function. Another study involving 147 women with
osteoarthritis found glucosamine to be no more effective than home exercises over
an eighteen-month period. A third study evaluated the effects of stopping
glucosamine after it was taken by participants for six months. In this
double-blind trial of 137 people with osteoarthritis of the knee, participants who
stopped using glucosamine (and unknowingly took placebo instead) did no worse than
people who stayed on glucosamine. In a fourth, large (1,583-participant) study,
neither glucosamine (as glucosamine hydrochloride) nor glucosamine plus
chondroitin was more effective than placebo. Another study also failed to find
benefit with glucosamine plus chondroitin. Finally, in a systematic review
including randomized trials involving 3,803 persons with osteoarthritis of the hip
or knee, researchers found that neither glucosamine alone, chondroitin alone, nor
the combination of glucosamine and chondroitin relieved pain. It appears that most
of the positive studies were funded by manufacturers of glucosamine products. Most
of the studies performed by neutral researchers failed to find benefit.

Many popular glucosamine products combine this supplement with methylsulfonylmethane (MSM). One study published in India reported that both MSM and glucosamine improved arthritis symptoms compared with placebo but that the combination of MSM and glucosamine was even more effective than either supplement separately.

Two studies reported that glucosamine can slow the progression of osteoarthritis. However, as with the positive studies of glucosamine for reducing symptoms, both of these studies were funded by a major glucosamine manufacturer.

Osteoarthritis results when irregular bone growth occurs at the edge of a joint, causing impaired movement of the joint and pressure on nerves in the area.

A three-year, double-blind, placebo-controlled study of 212 persons found indications that glucosamine may protect joints from further damage. Over the course of the study, persons given glucosamine showed some actual improvement in pain and mobility, while those given placebo worsened steadily. Furthermore, X rays showed that glucosamine treatment prevented progressive damage to the knee joint. A separate three-year study enrolling 202 people found similar results.

A follow-up analysis five years after the conclusion of the foregoing two studies found suggestive evidence that the use of glucosamine reduced the need for knee replacement surgery. However, the aforementioned study involving 222 persons with osteoarthritis of the hip failed to show any significant change on X ray findings following two years of glucosamine treatment compared with placebo.

Chondroitin sulfate. The supplement chondroitin
is often combined with glucosamine. Several studies also have evaluated
chondroitin used alone, with some positive results, both for improving symptoms
and for slowing the progression of the disease. On balance, however, the evidence
for chondroitin’s effectiveness for osteoarthritis remains inconsistent.

According to some double-blind, placebo-controlled studies, chondroitin may relieve symptoms of osteoarthritis. One study enrolled eighty-five people with osteoarthritis of the knee and followed them for six months. Participants received either 400 milligrams (mg) of chondroitin sulfate twice daily or a placebo. At the end of the trial, doctors rated the improvement as good or very good in 69 percent of those taking chondroitin sulfate but in only 32 percent of those taking placebo.

Another way of comparing the results is to look at maximum walking speed among participants. Whereas persons in the chondroitin group were able to improve their walking speed gradually over the course of the trial, walking speed did not improve in the placebo group. Additionally, there were improvements in other measures of osteoarthritis, such as pain level, with benefits seen as early as one month. This suggests that chondroitin was able to stop the arthritis from gradually getting worse. Good results were seen in a twelve-month double-blind trial that compared chondroitin with placebo in 104 persons with arthritis of the knee, and in a twelve-month trial of 42 participants.

Another study evaluated the intermittent or “on and off” use of chondroitin. In this study, 120 people received either placebo or 800 mg of chondroitin sulfate daily for two separate, three-month periods in one year. The results showed that even when it was taken intermittently, the use of chondroitin improved symptoms. Benefits were also seen in two short-term trials involving about 240 persons.

Generally positive results were also seen in other studies, including one that found chondroitin about as effective as the anti-inflammatory drug diclofenac. However, a large (1,583-participant) and well-designed study failed to find either chondroitin or glucosamine plus chondroitin more effective than placebo. When this study is pooled together with the two other best-designed trials, no overall benefit is seen. It has been suggested that chondroitin, like glucosamine, may show benefit primarily in studies funded by manufacturers of the product being tested.

Some evidence suggests that, like glucosamine, chondroitin might slow the progression of arthritis. An important feature of the foregoing study of forty-two persons was that the persons taking a placebo showed progressive joint damage over the year, but among those taking chondroitin sulfate, no worsening of the joints was seen. In other words, chondroitin sulfate seemed to protect from further damage the joints of those with osteoarthritis.

A longer and larger double-blind, placebo-controlled trial also found evidence that chondroitin sulfate can slow the progression of osteoarthritis. The study enrolled 119 people and lasted three years. Thirty-four of the participants received 1,200 mg of chondroitin sulfate per day; the rest received placebo. Over the course of the study, researchers took X rays to determine how many joints had progressed to a severe stage.

During the three years of the study, only 8.8 percent of those who took chondroitin sulfate developed severely damaged joints, whereas almost 30 percent of those who took placebo progressed to this extent. Similar long-term benefits were seen in two other studies, enrolling more than two hundred people.

Additional evidence comes from animal studies. Researchers measured the effects of chondroitin sulfate (administered both orally and via injection directly into the muscle) in rabbits, in which cartilage damage had been induced in one knee by the injection of an enzyme. After eighty-four days of treatment, the damaged knees in the animals that had been given chondroitin sulfate had significantly more cartilage left than the knees of the untreated animals. Taking chondroitin sulfate by mouth was as effective as taking it through an injection.

Looking at the sum of the evidence, it does appear that chondroitin sulfate may actually protect joints from damage in osteoarthritis. However, the scientific record suffers from a paucity of truly independent researchers.

S-adenosylmethionine. A substantial body of scientific evidence
indicates that S-adenosylmethionine (SAMe) can relieve symptoms of
arthritis. Numerous double-blind studies involving more than one thousand
participants suggest that SAMe is approximately as effective for this purpose as
standard anti-inflammatory drugs. However, there is no meaningful evidence that
SAMe slows the progression of the disease.

One of the best double-blind studies enrolled 732 persons and followed them for four weeks. Over this period, 235 of the participants received 1,200 mg of SAMe per day, while a similar number took either placebo or 750 mg daily of the standard drug naproxen. The majority of the participants had experienced moderate symptoms of osteoarthritis of either the knee or the hip for an average of six years.

The results indicate that SAMe provided as much pain-relieving effect as naproxen and that both treatments were significantly better than placebo. However, differences did exist between the two treatments. Naproxen worked more quickly, producing readily apparent benefits at the two-week follow-up, whereas the full effect of SAMe was not apparent until four weeks. By the end of the study, both treatments were producing the same level of benefit.

In a double-blind study that compared SAMe with the newer anti-inflammatory drug Celebrex, the drug worked faster than the supplement, but in time both were providing equal benefits.

Evidence regarding slowing the progression of arthritis is limited to studies involving animals rather than people.

Avocado-soybean unsaponifiables. Special extracts of avocado and soybeans called avocado-soybean unsaponifiables (ASUs) have been investigated as a treatment for osteoarthritis with promising results in studies enrolling several hundred people.

For example, in a double-blind trial, 260 persons with arthritis of the knee were given either placebo or ASU at 300 or 600 mg daily. The results over three months showed that the use of ASU significantly improved arthritis symptoms compared with placebo. There was no significant difference seen between the two doses tested. It does not appear that ASU can slow the progression of osteoarthritis.

Cetylated fatty acids. A type of naturally occurring fatty acid
called cetylated
fatty acids have shown growing promise for osteoarthritis.
They are used both as topical creams and as oral supplements. Three double-blind
placebo-controlled studies have found cetylated fatty acids helpful for
osteoarthritis. Two involved a topical product and one used an oral
formulation.

In one of the studies using a cream, forty people with osteoarthritis of the knee applied either cetylated fatty acid or placebo to the affected joint. The results over thirty days showed greater improvements in range of motion and functional ability among people using the real cream than among those using the placebo cream. In another thirty-day study, also enrolling forty people with knee arthritis, the use of cetylated fatty acid cream improved postural stability, presumably because of decreased pain levels. In addition, a sixty-eight-day, double-blind, placebo-controlled study of sixty-four people with knee arthritis tested an oral cetylated fatty acid supplement (the supplement also contained lesser amounts of lecithin and fish oil). Participants in the treatment group experienced improvements in swelling, mobility, and pain level compared to those in the placebo group. Inexplicably, the study report does not discuss whether or not side effects occurred. While this is a promising body of research, it is far from definitive.

Advertising claims for cetylated fatty acids go far beyond the existing evidence. For example, a number of Web sites claim that cetylated fatty acids are more effective than glucosamine or chondroitin. However, no comparison studies have been performed upon which such a claim could be rationally based.

Acupuncture. Acupuncture has shown inconsistent
benefit as a treatment for osteoarthritis. A 2006 meta-analysis (systematic
statistical review) of studies on acupuncture for osteoarthritis found eight
trials that were similar enough to be considered together. These studies enrolled
2,362 people. The authors of the meta-analysis concluded that acupuncture should
be regarded as an effective treatment for osteoarthritis.

However, one study comprised almost one-half of all the people considered in this meta-analysis, and it failed to find real acupuncture more effective than sham acupuncture. In this study, published in 2006, 1,007 people with knee osteoarthritis were given either real acupuncture, fake acupuncture, or standard therapy over six weeks. Though both real acupuncture and fake acupuncture were more effective than no acupuncture, there was no significant difference in benefits between the two acupuncture groups. In general, larger studies are more reliable than small ones. For this reason, it is always somewhat questionable when meta-analysis combines one large negative study and a number of smaller positive ones to come up with a positive outcome.

Another review, published in 2007, concluded that real acupuncture produces
distinct benefits in osteoarthritis compared to no treatment but that fake
acupuncture is effective for osteoarthritis too. When comparing real acupuncture
to fake acupuncture, the difference in outcome (while it might possibly be
statistically significant) is so trivial as to make no difference in real life. In
other words, virtually all of the benefit of acupuncture for osteoarthritis is a
placebo
effect.

Other Proposed Natural Treatments

A six-week, double-blind, placebo-controlled study of 247 persons with osteoarthritis of the knee evaluated a combination herbal product containing ginger and the Asian spice galanga (Alpinia galanga). The results showed that participants in the ginger and galanga group improved to a significantly greater extent than those receiving placebo. However, despite news reports claiming that this study proves ginger effective for osteoarthritis, this study only provides information on the effectiveness of the herbal combination. The two double-blind studies performed on ginger alone were small and produced contradictory results. Furthermore, another study found that massage combined with the topical application of essential oils made from ginger and orange was no better than massage plus olive oil in persons with osteoarthritis of the knee.

A three-week double-blind study of 220 people with osteoarthritis of the knee
found that the use of a cream containing the herb comfrey
reduced symptoms significantly more than a placebo cream.

The herb white
willow contains the aspirin-like substance salicin. A
two-week, double-blind, placebo-controlled trial of seventy-eight persons with
arthritis found evidence that willow extracts can relieve osteoarthritis pain.
However, another double-blind study enrolling 127 people with osteoarthritis found
white willow less effective than a standard anti-inflammatory drug and no more
effective than placebo. The likely explanation for these contradictory results is
that white willow at usual doses provides relatively modest benefits.

The supplement MSM, as described in a foregoing study, has shown promise for osteoarthritis when taken with glucosamine. Benefits were also seen in a twelve-week, double-blind, placebo-controlled trial of fifty people with osteoarthritis, utilizing MSM at a dose of 3 grams twice daily. However, in a comprehensive review of six studies involving 681 persons with osteoarthritis of the knee, researchers concluded it is not possible to convincingly determine whether or not MSM is beneficial.

Other treatments with incomplete supporting evidence from double-blind trials include Ayurvedic herbal combination therapy, boswellia, cat’s claw, a proprietary complex of minerals with or without cat’s claw, devil’s claw, proteolytic enzymes, rose hips, soy protein, and vitamin B3.

Traditional
Chinese herbal medicine has also shown some promise for
osteoarthritis. However, one study that compared a commonly used Chinese herbal
product (Duhuo Jisheng Wan) to the drug diclofenac found that the herb worked more
slowly than the drug, yet produced about an equal rate of side effects.

Growing but definitive evidence suggests that the natural substance hyaluronic acid may help reduce osteoarthritis symptoms when it is injected into an affected joint. However, there is absolutely no reason to believe that oral hyaluronic acid should help, and one study failed to show any significant benefit.

Incomplete and inconsistent evidence from human and animal studies only weakly
suggests that green-lipped mussel might alleviate osteoarthritis symptoms.
A badly designed human study hints that krill oil might be helpful as well. One
double-blind study involving dogs found some evidence of benefit with elk velvet
antler.

Numerous other herbs and supplements sometimes recommended for osteoarthritis include beta-carotene, boron, cartilage, chamomile, copper, dandelion, D-phenylalanine, feverfew, molybdenum, selenium, turmeric, and yucca. However, there is little to no evidence that these treatments are effective.

Other studies provide limited evidence that certain supplements proposed for osteoarthritis do not work. For example, a two-year double-blind study of 136 people with knee arthritis found vitamin E ineffective for either reducing symptoms or slowing the progression of the disease. In addition, a six-month, double-blind, placebo-controlled trial of seventy-seven people with osteoarthritis failed to find any symptomatic benefit with vitamin E. Similarly, in a large (almost four-hundred-participant), five-year, double-blind, placebo-controlled study, the use of injected mesoglycan failed to slow the progression of osteoarthritis. A fairly small study failed to find the enzyme bromelain helpful for reducing symptoms.

Prolotherapy is a special form of injection therapy that is
popular among some alternative practitioners. A double-blind, placebo-controlled
study evaluated the effects of three prolotherapy injections (using a 10 percent
dextrose solution) at two-month intervals in sixty-eight people with
osteoarthritis of the knee. At six-month follow-up, participants who had received
prolotherapy showed significant improvements in pain at rest and while walking,
reduction in swelling, fewer episodes of “buckling,” and better range of flexion,
compared to those who had received placebo treatment. The same research group
performed a similar double-blind trial of twenty-seven persons with osteoarthritis
in the hands. The results at six-month follow-up showed that range of motion and
pain with movement improved significantly in the treated group compared with the
placebo group.

Several double-blind, placebo-controlled studies suggest that pulsed
electromagnetic field therapy, a special form of magnet therapy, can improve
symptoms of osteoarthritis. One small study provides extremely weak supporting
evidence for the more ordinary form of magnet therapy: static magnets. A
subsequent, much larger study of static magnets failed to find real magnets more
effective than placebo magnets, but a manufacturing error may have obscured
genuine benefits (some people in the placebo group were accidentally given active
magnets). In another placebo-controlled trial, the use of a magnetic knee wrap for
twelve weeks was associated with a significant increase in quadriceps (thigh
muscle) strength in persons with knee osteoarthritis.

Limited evidence supports the use of bee venom injections for osteoarthritis. Hot
water therapy (balneotherapy), relaxation therapies, and various forms
of exercise, including hatha yoga and Tai Chi, have
also all shown some promise. However, for none of these therapies is the
supporting evidence convincing.

Herbs and Supplements to Use with Caution

Various herbs and supplements may interact adversely with drugs used to treat osteoarthritis, so one should be cautious when considering the use of herbs and supplements.

Bibliography

Arjmandi, B. H., et al. “Soy Protein May Alleviate Osteoarthritis Symptoms.” Phytomedicine 11 (2005): 567-575.

Brien, S., et al. “Systematic Review of the Nutritional Supplements Dimethyl Sulfoxide (DMSO) and Methylsulfonylmethane (MSM) in the Treatment of Osteoarthritis.” Osteoarthritis and Cartilage 16 (2008): 1277-1288.

Brismee, J. M., et al. “Group and Home-Based Tai Chi in Elderly Subjects with Knee Osteoarthritis.” Clinical Rehabilitation 21 (2007): 99-111.

Chen, C. Y., et al. “Effect of Magnetic Knee Wrap on Quadriceps Strength in Patients with Symptomatic Knee Osteoarthritis.” Archives of Physical Medicine and Rehabilitation 89 (2008): 2258-2264.

Clegg, D. O., et al. “Glucosamine, Chondroitin Sulfate, and the Two in Combination for Painful Knee Osteoarthritis.” New England Journal of Medicine 354 (2006): 795-808.

Deutsch, L. “Evaluation of the Effect of Neptune Krill Oil on Chronic Inflammation and Arthritic Symptoms.” Journal of the American College of Nutrition 26 (2007): 39-48.

Kawasaki, T., et al. “Additive Effects of Glucosamine or Risedronate for the Treatment of Osteoarthritis of the Knee Combined with Home Exercise.” Journal of Bone and Mineral Metabolism 26 (2008): 279-287.

Lee, M. S., M. H. Pittler, and E. Ernst. “Tai Chi for Osteoarthritis.” Clinical Rheumatology 27 (2008): 211-218.

Manheimer, E., et al. “Meta-analysis: Acupuncture for Osteoarthritis of the Knee.” Annals of Internal Medicine 146 (2007): 868-877.

Reichenbach, S., et al. “Meta-analysis: Chondroitin for Osteoarthritis of the Knee or Hip.” Annals of Internal Medicine 146 (2007): 580-590.

Tishler, M., et al. “The Effect of Balneotherapy on Osteoarthritis: Is an Intermittent Regimen Effective?” European Journal of Internal Medicine 15 (2004): 93-96.

Wandel, S., et al. “Effects of Glucosamine, Chondroitin, or Placebo in Patients with Osteoarthritis of Hip or Knee.” British Medical Journal 341 (2010): c4675.

How does Shakespeare present Juliet after the balcony scene?

The next time the audience sees Juliet after the balcony scene is when her nurse returns from a meeting with Romeo to learn what provisions he has made for his marriage to Juliet.  Juliet is excited, hopeful, and impatient, especially because the nurse is purposely delaying and teasing her.  Juliet says, exasperatedly, "How are thou out of breath, when thou hast breath / To say to me that thou art out of breath?" (II.5.33-34).  The nurse makes all manner of excuses to prolong Juliet's suspense: complaining about her aching head and back, talking about how handsome Romeo is, asking about the location of Juliet's mother.  Poor Juliet begins to lose patience with her, but recovers herself once she learns Romeo has sent word of their wedding.

Later, though Juliet seems to mourn the death of Tybalt sincerely, she also understands she owes her love to her husband.  She is quite thoughtful in Act III, Scene 2, when she wonders how "deceit should dwell / In such a gorgeous palace" (III.2.90-91).  Juliet knows she should hate the man who murdered her cousin, but also knows she ought to love the man who is her husband.  It's a terrible situation for her to be in, and her thoughtfulness (and even her wordplay and use of oxymora to describe Romeo's simultaneous treachery and beauty) conveys a sense of Juliet's maturity, even though she is but thirteen.

Still later, it is Juliet who visits Friar Lawrence's cell and commits to the plan to fake her own death as a means of escaping the wedding her father has planned for her to County Paris.  She is brave and independent, acting outside of her nurse's advice for what seems to be the first time in her life.  

What are spine, vertebrae, and disks?

Structure and Functions

The spinal column undergoes developmental changes from infancy to the adult state and then degenerative changes with aging. The alignment of the spinal column at birth is in the shape of a C curve, the fetus having been curled up. This forward-tilted curve is retained except in the neck and lower back. As the infant raises its head and attempts to see things, head control and vision gradually require the head to tilt back, resulting in a posterior curve at the neck. As children progress to standing and walking, the lower spine also develops a posterior curve (a normal lumbar lordosis). As individuals increasingly use the predominant upper extremities, these muscles become stronger and increase the pull on that side of the spine, resulting in a lateral curve (a normal scoliosis).

Humans generally have thirty-three vertebrae, but abnormalities can occur in their numbers, shape, alignment, density, and maturation. There are seven vertebrae in the neck or cervical area, twelve in the chest or thoracic area, five in the lower back or lumbar area, five usually joined together in the pelvic region to form the sacrum, and three or four rudimentary vertebrae partially fused to form the coccyx. The typical vertebra develops embryologically from two bone growth centers. The front of one bone growth center becomes the body and part of the arch, while the other bone growth center evolves into the spinous processes, the transverse processes, the articular processes, and the back portion of the arch.

The thirty-three vertebrae of the spine have various defined parts and characteristics. The oval or round vertebral body has a spongy center surrounded by a dense bone. Above and below it are layers of cartilage. Lack of the mineral calcium reduces the density of the bone, resulting in osteoporosis. This condition may occur in postmenopausal women, causing pain, fractures, and kyphosis (a thoracic humpback). The pedicle portions of this anterior arch have an upper and lower notch called the intervertebral foramina, through which the spinal nerves exit from the spinal canal. At the junction of pedicle and lamina are projections upward and downward that form the articular processes, or joints. The alignment and direction of these joints vary with the spinal region and serve to control spinal motion. The transverse processes assist in the movement of muscles and at the chest level act as links between the ribs. There are generally twelve thoracic vertebrae and twelve ribs. On occasion, an extra cervical rib may be present; this extra rib narrows the exit space at the neck and can pinch the cervical nerves and blood vessels.

The upper two cervical processes are different from all other vertebrae. The first cervical vertebra supports the head and is called the atlas. Instead of a body, it has an enlarged anterior arch and a groove on which the head rests. Its transverse processes are long, but its spinous process is a little knob. The second cervical vertebra is also unique, with an upward projection called the dens that is like a pole fitting into the ring of the first cervical vertebral arch. It represents the body of the first cervical vertebra. This pole and ring permit the head to rotate.

The cervical transverse processes or lateral projections have holes, the transverse foramina, through which the vertebral arteries send blood to the brain. As one progresses downward, the vertebrae become larger and bear more weight. The thoracic vertebrae have their joint surfaces in the frontal plane, and the transverse processes are solid. The ribs share half of the joint surfaces with the adjoining vertebrae, except for the first, tenth, eleventh, and twelfth vertebrae; these vertebrae join only their corresponding ribs. As one continues down the spine, the spinous processes become more slender and project downward, almost touching one another. The lower thoracic vertebrae are closer to the lumbar vertebrae in appearance.

The lumbar vertebrae are more massive, carry more stress, and support the weight of the body. The transverse processes in this region are thinner but longer, increasing the leverage action for muscles. The joint surfaces tilt upward, backward, and toward the center, opening the joint space when one bends forward. This action permits side bending, increasing the side pressures on the disks. The five sacral vertebrae are fused, with small ridges representing the sites of fusion. Small openings allow the upper four sacral nerves to exit the spine. The sacrum contributes the back portion of the pelvis. The coccyx, or tailbone, is composed of three or four rudimentary vertebrae, with the first distinct and separate from the other two or three, which are fused. The back of the spine is layered with muscles going to the upper extremities, with long vertical muscles underneath, intermediate-length muscles under these, and the deepest muscle groups closest to the spine and only two or three vertebrae in length.

Vertebrae are separated by washers called disks. The central portion of a disk is a gel-like substance, the nucleus pulposus, which offers hydraulic cushioning and allows some movement. This substance is enclosed in a ligamentous covering called the annulus fibrosis. Disks contribute approximately one-fourth of body length, can add about eight degrees in motion per vertebra, and can alter their shape to accommodate the solid vertebrae when the body is bent. The nucleus pulposus is 70 to 80 percent water, and about 14 kilograms (30 pounds) of pressure must be exerted constantly by ligaments to maintain the shape of the disk. Dehydration, aging, compressive forces, and simply a day of normal activity can temporarily reduce the amount of the watery nucleus pulposus, increase the bulging of the disks, and shorten one’s stature.

The spinal cord
connects the peripheral structures of the body to the brain and the nerve cells in the spinal cord itself. Until about the third month of life, the spinal cord occupies the entire length of the spinal canal. The vertebrae grow faster than the spinal cord, however, and later in life it occupies two-thirds of the length of the spinal canal (approximately 42 to 45 centimeters) and ends at about the second lumbar vertebra. The coverings on the cord continue as the filum terminale, which is attached to the sacral vertebrae.

There are three coverings of the spinal cord within the spinal canal. The outermost, toughest, and fibrous covering, called the dura, is separated from the bony surfaces by fat and blood vessels. The spinal cord is covered by a thin layer called the pia that enters into the spinal cord and separates various portions of the cord. Surrounding the pia is a protective fluid, the spinal fluid, which is held in place by the arachnoid layer; this fluid can be aspirated for analysis, as in a lumbar puncture, or spinal tap. The nerves exiting from the spinal cord are also segmental. There are only seven cervical vertebrae but eight cervical nerves. The eighth cervical nerve exits below the seventh cervical vertebra, and thereafter all roots from the vertebrae leave below the corresponding vertebra. These segmental nerves then join, divide, send messages to the brain and other organs, and control bodily functions and motion.

Ligaments run vertically in front of the vertebral bodies (the anterior longitudinal ligament) and in back of the vertebral bodies and within the spinal canal (the posterior longitudinal ligament). These ligaments support the vertebrae and disks and limit excessive motion forward and backward. The posterior longitudinal ligament ceases at about the fourth lumbar vertebra, and thus farther down the spine the fibrous rings about the disks are weaker, permitting herniations. Such leakages from the disks may press on nerve roots exiting at these levels and cause pain. These ruptures of the disks occur mostly when lifting with the trunk bent forward and sideways. There are additional ligaments between the spinous processes at the tips (the supraspinous ligament) and along the length of the spinous processes (the interspinous ligament). The portion of the arch between the spinous processes and the transverse processes is the lamina. Between the laminae are the ligamentum flavum. The interspinous ligament, ligamentum
flavum, and nucleus pulposus have no pain fibers. The laminae and disks may be removed when disk surgery is performed, and pieces of bone from the hip may be used to fuse and reduce motion at this level.

Motion between each vertebra is about eight degrees. Motion is enhanced by the facets, vertical bony projections with joint surfaces. They are structured like the other joints of the body, and thus are subject to irritation and arthritic changes. Flexion of the trunk opens the spaces in the lumbar joints and allows side bending and rotation in the same direction. Extension of the trunk compresses and limits motion in these facets.

The blood supply to the spinal cord and the surrounding tissues diminishes progressively downward. Excessive activity can lead to insufficient circulating blood to these nerves and give rise to symptoms in the lower extremity called intermittent claudication. The front portion of the spinal cord contains motor nerve cells, leading to the trunk and the muscles of the extremities, that can be inhibited or activated by impulses. The lateral areas of the spinal region contain messenger tracts and the autonomic nervous system. The back portion of the spinal cord has sensory structures that carry messages of pain, temperature, position, and touch to the brain. The different levels within the spinal cord connect to different segmental structures of the body. The fifth cervical nerve down to the first thoracic nerve connect to the upper extremities, and the second lumbar to second sacral roots connect to the lower extremities. Compression of these nerve roots at the spine may cause symptoms in areas distant from the spine.

Disorders and Diseases

The anatomy of the trunk regulates the erect, or standing, posture. It is influenced by the structure of the vertebrae and extremities and even by the tilt of the head. It is also influenced by cultural factors, emotion, habits, and occupation. Good posture involves standing straight with the head up, the shoulders back and up, the stomach in, and the hips and knees straight. This position also is most efficient in energy expenditure, since it requires the least amount of muscle activity in order to balance the weights in the front and back of the trunk, as well as the weights on the left and right sides of the body. Looking at the front of the body, the central gravitational, or weight-bearing, line falls in line with the nose and between the pelvis, knees, and ankles. From the back, the gravitational line follows the center of the head, the spinous processes, the gluteal fold between the buttocks, and between the knees and ankles. The weight stresses should be balanced between the right side and the left side of the body and between the front and the back. The head should be maintained so that the eyes and the labyrinth in the inner ear are level. Any deviations cause
imbalance in the trunk, resulting in muscle strain, ligament sprains, pain, and possibly deformities. Abnormalities in posture and gait may be attributable to muscle imbalance, deformities at birth, problems in development, disease, or surgical procedures.

There are several birth defects that affect the spine. Occasionally, during embryonic development
, the two bone growth regions that form a vertebra do not fuse together, causing an opening in the arch in the back called spina bifida. Spondylolysis occurs when the articular process remains unattached. Ligaments, muscles, and tendons are unable to attach to these areas securely, and the result is weakness in the vertebra and a reduction in stability. Occasionally, this weakness permits the upper vertebra to slide forward, a condition called spondylolisthesis. The misalignment and narrowing of the spinal canal can compress the nerve structures within it, a condition known as spinal stenosis. The lower cervical and lower lumbar regions, which need more nerve tissue to supply the extremities, are especially vulnerable to pressure symptoms.

Inequality in leg lengths or pain in the lower extremities, upper extremities, abdomen, chest, or neck can lead to compensatory reactions in the trunk. These may then cause misalignment in the spine with side deviations (scoliosis), backward deviations (kyphosis, or humpback, in the thoracic area), and forward deviations (lordosis in the low back). Other contributing factors are overuse, muscle spasm or weakness, birth defects, developmental abnormalities, diseases, aging, and trauma. Some misalignments occur after surgery on the chest, back, or abdomen. Idiopathic scoliosis (scoliosis of unknown cause) may occur in adolescent girls; when it is severe, lung and heart functions can be impaired. Temporarily increased lordosis can occur in pregnancy, to compensate for the extra weight in the abdomen. Lordosis may be permanent because of structural changes in the spine, pendulous abdomen and/or breasts, or poor muscle balance. Therefore, back problems may be caused by poor posture, behavior, occupation, and structural, neurologic, or muscular factors. Pain located only
in the back is generally attributable to poor posture, trauma, or inflammation. If pain extends below the knees, the cause may be nerve pressure at the fifth lumbar or first sacral nerve roots. Bladder and rectal sphincter disturbances may indicate sacral nerve or cord involvement and may require immediate surgical care.

The body’s center of gravity is in the front portion of the second lumbar vertebra. Thus, the compressive force of body weight is increased when one lifts an object with the arms in front of the trunk. The greater the distance of the object from the center of the body, the greater the need for the back muscles to contract. Lifting a 45-kilogram (100-pound) object may require a 545-kilogram (1,200-pound) muscle pull and compressive force. The posterior longitudinal support for the disks that is provided by ligaments narrows in the sides at the level of the fourth and fifth lumbar vertebrae. Herniations through the fibrous disk ring at these levels are more likely, and a ruptured disk can pinch the nerves exiting at these levels.

Stresses that bear on the spine are categorized as compressive, shearing, elongating, or rotational. Compressive forces may involve the muscles, disks (possible ruptures), vertebrae (fractures), and the facet joints. Shearing stress may lead to forward slippage of the fourth or fifth vertebra from the segment below. This is most common in individuals with incomplete bony union of vertebrae. Rotatory stress may affect the joints, the facets of the spine, the short spine muscles, or the ligaments. On rare occasions, an elongating stretch or traction may strain muscles and sprain or tear ligaments.

Perspective and Prospects

Examinations of the spine usually include the history of the problem: whether it is sudden or gradual and whether it is influenced by certain activities or climates. The physician checks the patient’s posture for abnormal curvatures and determines whether they are fixed or functional. Functional curves disappear when the patient is lying down. The gait should be evaluated for symmetry, balance, and deviations. The physician will measure leg lengths for inequalities, the circumference of the chest for rib flare, and the circumferences of extremities for swelling or shrinkage. Next, the trunk’s range of motion will be evaluated, followed by palpation to discover tender spots and muscle spasms.

With spinal problems, a full examination of the entire body is indicated since pain can be referred to the back from other organs. Changes in function, sensation, and motor strength can indicate spinal cord or nerve involvement. Simple X rays of the spine will indicate alignment of the vertebrae, bone density, fracture lines, extraneous bone growth, cartilage thickness, and unusual soft tissue densities caused by hemorrhage or calcification. For problems other than bone and cartilage tissue involvement, a computed tomography (CT) scan or magnetic resonance imaging (MRI) may be needed; these techniques provide images of the area to be examined that are at different levels or depths. In 2013, reserachers at the University of Zurich published a study showing that spinal cord injury can cause irreversible tissue loss within forty days of sustaining injury.

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