Nervous Tissue Glial Cells

Neuroglia, also called glia or glial cells, are non-neuronal cells of the nervous system. They compose a rich support system that is essential to the operation of nervous tissue and the nervous system. Unlike neurons, glial cells do not have axons, dendrites, or conduct nerve impulses. Neuroglia are typically smaller than neurons and are about three times more numerous in the nervous system. Glia perform a number of functions in the nervous system, including physically supporting the brain; assisting in nervous system development, repair, and maintenance; insulating neurons; and providing metabolic functions for neurons. Types of Glial Cells There are several types of glial cells present in the central nervous system (CNS) and peripheral nervous system of humans. They each serve different purposes for the body. The following are the six main types of neuroglia. Astrocytes Astrocytes are found in the brain and spinal cord and are 50 times more plentiful than neurons and the most abundant cell type in the brain. Astrocytes are easily identifiable due to their unique star-shape. The two main categories of astrocytes are protoplasmic and fibrous. Protoplasmic astrocytes are found in the gray matter of the cerebral cortex, while fibrous astrocytes are found in the white matter of the brain. The primary function of astrocytes is to provide structural and metabolic support to neurons. Astrocytes also aid in transmitting signals between neurons and brain blood vessels to control the intensity of blood flow, though they do not do the signaling themselves. Other functions of astrocytes include glycogen storage, nutrient provision, ion concentration regulation, and neuron repair. Ependymal Cells Ependymal cells are specialized cells that line the cerebral ventricles and central canal of the spinal cord. They are found within the choroid plexus of the meninges. These ciliated cells surround capillaries of the choroid plexus. Functions of ependymal cells include CSF production, nutrient provision for neurons, filtration of harmful substances, and neurotransmitter distribution. Microglia Microglia are extremely small cells of the central nervous system that remove cellular waste and protect against the invasion of harmful microorganisms such as bacteria, viruses, and parasites. Because of this, microglia are thought to be a type of macrophage, a white blood cell that protects against foreign matter. They also help to reduce inflammation in the body through the release of anti-inflammatory chemical signals. Additionally, microglia protect the brain by disabling malfunctioning neurons that become injured or diseased. Satellite Cells Satellite glial cells cover and protect neurons of the peripheral nervous system. They provide structure and metabolic support to sensory, sympathetic, and parasympathetic nerves. Sensory satellite cells are often linked to pain and sometimes even said to be associated with the immune system. Oligodendrocytes Oligodendrocytes are central nervous system structures that wrap around some neuronal axons to form an insulating coat known as the myelin sheath. The myelin sheath, composed of lipids and proteins, functions as an electrical insulator of axons and promotes more efficient conduction of nerve impulses. Oligodendrocytes are generally found in the brains white matter, but satellite oligodendrocytes are found in gray matter. Satellite oligodendrocytes do not form myelin. Schwann Cells Schwann cells, like oligodendrocytes, are neuroglia that create the myelin sheath in peripheral nervous system structures. Schwann cells help to improve nerve signal conduction, nerve regeneration, and antigen recognition by T cells. Schwann cells play a vital role in nerve repair. These cells migrate to the site of injury and release growth factors to promote nerve recovery, then myelinate newly generated nerve axons. Schwann cells are being heavily researched for their potential use in spinal cord injury repair. Both oligodendrocytes and Schwann cells indirectly assist in the conduction of impulses, as myelinated nerves can conduct impulses quicker than unmyelinated ones. White brain matter gets its color from large numbers of myelinated nerve cells. Sources Purves, Dale. â€Å"Neuroglial Cells.†Ã‚  Neuroscience | 2nd Edition, U.S. National Library of Medicine, 2001.Sofroniew, Michael V., and Harry V. Vinters. â€Å"Astrocytes: Biology and Pathology.†Ã‚  SpringerLink, Springer-Verlag, 10 Dec. 2009.

Comparative Essay Catcher and Breakfast Club - 1644 Words

The Catcher in the Rye and The Breakfast Club Various pieces of literature and entertainment exhibit similar characteristics in their writing style, themes, and portrayals. These features are in each piece to enhance the reading and viewing. The novel The Catcher in the Rye by J.D. Salinger, and the movie The Breakfast Club directed by John Hughes, are two works that are similar in some significant aspects. Both compositions overflow with the theme of teenage rebellion, use rich vernacular, and portray adults as corrupt and unreasonable. These resemblances are recognized through the character’s actions and opinions in both pieces. A prominent theme in the novel The Catcher in the Rye is teenage rebellion. Throughout the novel, Holden†¦show more content†¦A common word Holden employs the use of is ‘phony’. This is seen when he says â€Å"For instance, they had this headmaster, Mr. Haas, that was the phoniest bastard I ever met in my life† (Salinger, 13). Other uses of vernacular include the words galoshes, crumby, flit, dough, chisel, swanky, and swell. These words add to the emotion and descriptive quality of the novel. â€Å"Some guy next to me was snowing hell out of the babe he was with† is an example of vernacular that helps to describe Holden’s thoughts (Salinger, 142). An example of slang used to add detail to the writing is, â€Å"I had a feeling old Ackleyd probably heard all the racket and was awake† (Salinger, 46). The particular language selected in the writing of The Catcher in the Rye also helps the reader relate to the main character, and is ther efore an effective style of writing in many situations. The movie The Breakfast Club teems with vernacular that adds value its descriptive language. Much of the vernacular, like The Catcher in the Rye, is used according to the time period the pieces were released. A prime example of vernacular is when Bender imitated his father saying, â€Å"Stupid, worthless, no good, goddamn, freeloading son of a bitch. Retarded, big mouth, know-it-all, asshole, jerk† (Hughes, 1985). Other pieces of vernacular include babbling, hot beef injection, totaled, nads,Show MoreRelatedStephen P. Robbins Timothy A. Judge (2011) Organizational Behaviour 15th Edition New Jersey: Prentice Hall393164 Words   |  1573 Pagesbehavior Study of organizational behavior Unit of analysis Output Psychology Individual Social psychology Group Sociology Formal organization theory Organizational technology Organizational change Organizational culture Comparative values Comparative attitudes Cross-cultural analysis Organization system Anthropology Organizational culture Organizational environment Power 14 CHAPTER 1 What Is Organizational Behavior? Psychology Psychology seeks to measure, explain,

How to Stay Calm free essay sample

Sometimes situations do not go as expected. A good day may turn bad, everything may suddenly go wrong. Needless to say, its difficult to stay calm in such situations. We tend to become confused, panic or even heated by anger. That wont help you much to get out of the situation though. Handling a bad situation in such condition will just make it worse; you are more likely to make mistakes. Thats why Its Important to stay calm. By staying calm, you will be able to Judge the situation wisely and take the appropriate actions.But how do you stay calm when the situation goes bad? How do you calm your nerves while the world around you Is falling down? I believe there are some simple things you can do. Here are 26 tips ; pick the ones that work for you: Take a deep breath. Do nothing for 5 minutes. We will write a custom essay sample on How to Stay Calm or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page Take a nap. Take a shower. Listen to comforting music. Listen to natural sounds. Play music. Share to a positive friend. Meditate. Ask Whats the next action? and focus on only that one thing. Go to nature (mountain, beach, etc. ). Ride a bike.Talk about other topics. Drink a bottle of water. Play games Oust for a while! ). Go eat with someone who is not part of the situation. Exercise. Read spiritual texts. Listen to spiritual audio programs. Unplug the Internet. Take a cup of coffee. Say to yourself, This situation is not as bad as It looks. Many people have handled situations worse than this successfully. Be grateful for what you still have (Instead of looking at what you dont have). Be grateful for what you can learn from the situation. Take a walk around a park.Smile. How to Stay Calm By vividness will Just make it worse; you are more likely to make mistakes. Thats why its important do you calm your nerves while the world around you is falling down? I believe there Share too positive friend. Unplug the Internet. Say to yourself, This situation is not as bad as it looks. Many people have handled situations worse than this successfully. Be grateful for what you still have (instead of looking at what you dont have). Be grateful for what you can learn from the situation.

Lawrences Works Details How The Mendicant Orders Arose Before A

Lawrences works details how the mendicant orders arose before and during the thirteenth century. Europe supported the establishment of the church, implemented change and reform leading to heresy and separation. Lawrence regards the revolutionary situation (page 225), as one resulting partly by the growth of towns and the general population. Due to social changes within medieval Europe itself it sought control and threatened the stability of the Church and of the religious beliefs of the people. In a way, the rise of the mendicant orders at this time is an answer to the problems in this situation. Mendicant orders are seen by Lawrence as a revolutionary answer to a potentially revolutionary situation (page 225) because of the long-term effect to help preserve the church hierarchy. This sometimes was in conflict and even become partly incorporated into that hierarchy themselves. Although, to some extent the mendicant orders were innovative, they cannot be seen as itself revolutionary. In order to be considered revolutionary, they would have had to overthrow the previous church order and perhaps replacing it with a new one. But mendicant order did nothing of the sort. The establishment of monasteries and schools allowed them to later become part of the Catholic Church, government system. The Friars were well trained in theology and pastoral skills which is why they were chosen by the papacy to completely destroy the religious beliefs that opposed the orthodox views (page 188). At this time religion in the West was a relatively new concept. The friars are noted to have had some importance in the Inquisition: suppressing the heresy (Websters New World Dictionary, 249). Developing out of measures to combat the dualist heresies rampant in France and in northern and central Italy by the middle of the twelfth century. (Page 189). Here the Church used its various means to combat the Cathars and others who opposes the belief of Dogma [that body of theological doctrines authoritatively affirmed (Websters New World Dictionary, 146)] in that area. The Dominicans played a major role in the Albigensian Crusade directed against the Cathars to wipe them out. Dominicans also played a part in the development of the Inquisition. The Frascisians were drawn into enterprise, though at first on a more limited scale. (Page 190) although it wasnt until Pope Innocent IV, that the Fransciscans began to play an important role in the Inquisition (page 191). Nevertheless, judging from just this it can be seen that the role of the Friars could hardly be considered revolutionary. Instead of overturning the established order, the friars supporting it, and even encouraged the use of violence against those who threatened the heretics. Their presence resulted in reforms in learning and in the organization of the Church that accommodated as a part of the clergy. The friars role counteracted the threats made to the Church by enabling it to adapt new ideas. What the friars did do, then, was to serve as an important force for reform. The Dark Ages were over, and the practices that works in earlier times were less likely to work for the purpose of the Church as time went on. Medieval towns were becoming cities with the rise of commercial class. Better education that before, they were in a better position to criticize corruption within the clergy itself. Thus, the power of the clergy and the church was also in question. It was only a question of time before the secular nobility would become more and more independent of the church. We can see that even at the time of Albigensian Crusade, political and military leaders such as the Count of Toulose were not hesitant to openly oppose church policies. In intellectual, economic and social uproar, the cities were productive areas for heresy. The literate a laity, who formed the upper strata of the new urban society aware of the educational and moral shortcomings of secular clergy, were a natural forcing ground both for orthodox criticism of the Church and for radical dissent. (Page 3). For this reason, the Church was faced with a potentially revolutionary situation. The situation developed to an extent not again until the Reformation. So the Cathars in southern France were able, to field their own clerical hierarchy, and eventually oppose to

A Knights Tale analysis of a film trailer Essay Example

A Knights Tale analysis of a film trailer Essay Example A Knights Tale analysis of a film trailer Paper A Knights Tale analysis of a film trailer Paper Essay Topic: Film Film trailers are a most effective and popular way to promote and advertise a film. They are shown at cinemas and on TV to catch the audiences attention and to let the viewer know what the film is about. They are often shown many months before the film is due for release to let fans know what their favourite stars are working on next. Sometimes when a series of films are planned the sequel trailer is shown at the same time as the first episode is being screened. An example of this is Lord of the Rings and Harry Potter. I have chosen to analyse the film trailer, which was used to promote A Knights Tale. I decided to use this trailer because A knights tale was one of my favourite films of last year! I like this film because it is so different. It is a historical film but it also is very funny and entertaining. It is a not-too-serious look at the world of medieval knights, chivalry and tournaments. All the historical details are there but they are given a modern twist, which appeals. A Knights Tale seems to appeal to a wide range of target audiences. My first reaction would be to say it is targeted at teenage boys and men because of the action and the big football link, but also the film could appeal to females as well because of the main star Heath Ledger. There is a hint of a love story, which instantly attracts girls. The film is rated, as a PG so would also be suitable as a family film. This film can be viewed on many levels. Very obviously it has action, but also quite subtle humour and it can be seen as a satire or parody on football. The Knights Tale is a new take on the Cinderella fairy tale. Its a rag to riches tale, which has eternal appeal to all ages. A Knights tale is set in medieval Europe. The people and the events in the trailer make this very obvious. Although it is medieval, it has a very modern twist because the characters behave in a modern way. The clothes worn while medieval looking would in some cases transfer really well into todays fashion. It is not a serious medieval film, but a fun, love and action story about dreams. The whole film has a very big link to modern day football or boxing. This was the sport of the time and the main source of entertainment. Even down to the last details it compares to football. In the trailer we see big roaring crowds, singing, cheering and chanting for their favourite knight. The supporters wear the colours of the knight and their shield, just like a supporter would wear a football strip. You also see people selling food, drink and flags just like hot dog vendors at a match. In the trailer you can see the crowd warming up and chanting the winners name. There is one clip in the trailer showing a helmet flying into the audience. It is made in slow motion and the crowd are jumping up to grab it just alike a football kicked into the crowd. Another clip shows the crowd doing a Mexican wave. This is linked to football because it first originated in the 1970 World Cup in Mexico. Just like football, jousting is in tournaments and finally leads up to a big world cup. The clips chosen, like most trailers, show off the most exciting parts of the film. At the start it is building up excitement with the crowd anticipating the sport. There is a big variety of film clips and it tells the basis of the plot, without giving too much away. This leaves the viewers with an idea of the story but still left wanting to no more. There are also a few hints of the romance in the trailer, which catches peoples attention. The trailer also identifies the main characters. Heath Ledger, who is quite well known, was main star. He has been seen in such films as The Patriot and Ten things I hate bout you. In this film he has the leading role, William Thatcher. In the start of the trailer you see him as a young peasant boy and then later an adult making his dream of becoming a knight into reality. The trailer concentrates mainly on him but you recognise his friends, a girl he might fall for and the bad guy. William is obviously the good guy. He wears quite poor clothes along with his friends because they are the knights servants and obviously peasants. One of his special friends is the poet and well-known writer Geoffrey Chaucer, who is famous for writing the Canterbury Tales, one of which is called The Knights Tales. The baddy (Adimar) is identified because he looks rich and wears dark clothes, mainly black. Perhaps this is to represent the dark side of his character. The girl Jocelyn is shown to wear exotic clothes, with bright pastel colours. The trailer is as action packed as the film with lots of images flashed onto the screen giving the impression of pace, excitement and combat; knights jousting, crowds roaring, swords clashing and heralds introducing champions. There is very little text because the emphasis is on action.

How does the Media Shape Our Development of Moral Judgment Research Paper

How does the Media Shape Our Development of Moral Judgment - Research Paper Example How this is happening is the way in which the youth is spending a lot of their time with the media due to their easy access to explicit content. With added convenience children can find stories that encompass violence, sexual promiscuity, theft, and greed in numerous media outlets such as fictional programming, a number of reality shows, music, and through the Internet. Research primarily looks at the effects on morality due to the media by looking at the underlying moral decision making that affects their behaviors. As far as children are concerned their moral development follows a very conventional developmental path. When these children, typically under the age of eight, are presented with an ethical dilemma their judgment of right and wrong is highly reliant on whether their action results in a reward or punishment. However as children mature their judgment takes into account a larger amount of factors, intentions and motives which revolve around recognition of the many conflicti ng rules inherent in moral dilemmas. Such a change can be attributed to the fact that their moral reasoning becomes much more flexible and ‘other’ oriented. ... A majority of the children’s perception found unjustified aggression to be wrong however children who watched programs that encompassed fantasy violence, such as Power Rangers, were more inclined to judge the ‘justified’ aggression being morally correct. Research reinforces this notion seeing as how violence in famous superhero cartoons is mostly seen as justified. Hence in the Krcmar study, it was observed how children who watched fantasy violence and those who watched realistic entertainment violence, such as Cops, were seen to display a lesser advanced moral reasoning strategies, with their primary focus being on rules and how prominent the presence or absence of punishment was as far as moral dilemmas was concerned. In another study which focuses on a similar pattern it was found that children who watched fantasy violence frequently were more likely than those who were light viewers to perceive justified violence as being morally correct. The heavy exposure to fantasy violence also led to these children having a lesser advanced role-taking abilities, which consequently affected their moral reasoning skills, making them less sophisticated (Wilson, 2008). A study also focused on looking at the influence the family had on a child’s television viewing and moral reasoning. It was found that if parents stressed and emphasized on communication within a family the children were less likely to watch fantasy violence that was shown on television and therefore develop higher moral reasoning skills and vice versa (Livingstone, 1996). A longitudinal study conducted by Judy Dunnn and Claire Hughes looked at how the media had an impact on the moral development of â€Å"hard-to-manage† preschoolers when compared with

Kant and Hume on Morality Essay Example | Topics and Well Written Essays - 1250 words

Kant and Hume on Morality - Essay Example Later on these views are critically analysed to establish which point of view is better. Kant Kant argues for an a priori basis for morality in his work. The central concept is the â€Å"categorical imperative†. The author sees morality springing from nothing other than pure reason. This contradicts Hume directly who held that reason could never be ground to justify morality. However, Kant states that people’s personhood and dignity should always be respected. People can be treated as both a means and an end simultaneously but not merely as means. Lying has been used as an example by Kant to justify his notion. He considers lying to be immoral under any circumstances and for any purpose at all. Actions must be universal according to Kant. Moreover, morality cannot be treated as an issue of mere preference or taste. Kant has utilised maxims to establish the a priori basis for morality. Volition is wanted that is a rule that is followed by an intentional act. He argues th at any moral actions must fall into one of the five categories that constitute the categorical imperative. ... thing: â€Å"can be regarded as good without qualification, except a good will.† 1 Good will is seen as the beacon that guides a person to doing the right thing. In case that a person fails to do a good thing, the good will has not failed. Instead the ability to carry out the good will has failed. Following the establishment of good will, Kant moves to establish moral obligations and duty. He delineates that many acts are done out of personal consideration rather than for the sake of morality. A shopkeeper who uses honest prices is doing so because he wishes to be respected by his customers and not merely for the sake of morality alone. Kant believes that such a person â€Å"deserves praise and encouragement, but not esteem.† 2 People who commit the greatest moral acts are the ones who commit such actions without regard for reward. Kant affirms that these are the only people who are actually acting morally. Durkheim’s altruistic suicide is seen by Kant as an este emed action because the man giving up his life gains nothing out of it. As per Kant: â€Å"Duty is the necessity to act out of reverence for the (moral) law.† 3 Following the moral law in intrinsic sense of right and wrong is a person’s greatest obligation. Hence, morality is a priori as per Kant. He further proposes four situations that demand decision making to with respect to duty. These are: actions contrary to duty for example stealing; dutiful actions carried out in fear of reprisal or penalties for example paying taxes, not violating traffic signs; dutiful actions that are carried out because of the agent’s prior inclination to them generally because such actions are pleasurable for example any labour of love; dutiful actions that contradict personal inclination for example not resorting to suicide