How Your Immune System Works Essays, Book Reports, Term Papers

This essay How Your Immune System Works Essays, Book Reports, Term Papers has a total of 1160 words and 6 pages.

How Your Immune System Works How the Immune System Works The immune system defends the body from attack by "invaders" recognized as foreign. It is an extraordinarily complex system that relies on an elaborate and dynamic communications network that exists among the many different kinds of immune system cells that patrol the body. At the "heart" of the system is the ability to recognize and respond to substances called antigens whether they are infectious agents or part of the body, which are called self anitgens. T and B Cells Most immune system cells are white blood cells, of which there are many types. Lymphocytes are one type of white blood cell, and two major classes of lymphocytes are T cells and B cells. T cells are critical immune system cells that help to destroy infected cells and coordinate the overall immune response. The T cell has a molecule on its surface called the T-cell receptor. This receptor interacts with molecules called MHC or major histocompatibility complex. MHC molecules are on the surfaces of most other cells of the body and help T cells recognize antigen fragments. B cells are best known for making antibodies. An antibody binds to an antigen and marks the antigen for destruction by other immune system cells. Other types of white blood cells include macrophages and neutrophils. Macrophages and Neutrophils Macrophages and neutrophils circulate in the blood and survey the body for foreign substances. When they find foreign antigens, such as bacteria, they "engulf" and destroy them. Macrophages and neutrophils destroy foreign antigens by making toxic molecules such as reactive oxygen intermediate molecules. If production of these toxic molecules continues unchecked, not only are the foreign antigens destroyed, but tissues surrounding the macrophages and neutrophils are also destroyed. For example, in individuals with the autoimmune disease called Wegener's granulomatosis, overactive macrophages and neutrophils that invade blood vessels produce many toxic molecules and contribute to damage of the blood vessels. In rheumatoid arthritis, reactive oxygen intermediate molecules and other toxic molecules are made by overproductive macrophages and neutrophils invading the joints. The toxic molecules contribute to inflammation, which is observed as warmth and swelling, and participate in damage to the joint. MHC and Co-Stimulatory Molecules MHC molecules are found on all cell surfaces and are an active part of the body's defense team. For example, when a virus infects a cell, a MHC molecule binds to a piece of a virus or antigen, and displays the antigen on the cell's surface. Cells that have the capability of displaying antigen with MHC are called antigen-presenting cells. Each MHC molecule that displays an antigen is recognized by a matching or compatible T-cell receptor. Thus, an antigen-presenting cell is able to communicate with a T cell about what may be occurring inside the cell. However, for the T cell to respond to a foreign antigen on the MHC, another molecule on the antigen-presenting cell must send a second signal to the T cell. A corresponding molecule on the surface of the T cells recognizes the second signal. These two secondary molecules of the antigen-presenting cell and the T cell are called co-stimulatory molecules. There are several different sets of co-stimulatory molecules that can participate in the interaction of antigen-presenting cell with a T cell. Once the MHC and the T-cell receptor interact, and the co-stimulatory molecules interact, there are several possible paths that the T cell may take. These include T cell activation, tolerance, or T cell death. The

Read essay without registering

Donate an essay now and get the full essay emailed you




Acceptable files: .txt, .doc, .docx, .rtf

Email Address

Related Essays

Watergate1 Watergate, designation of a major U.S. political scandal that began with the burglary and wiretapping of the Democratic party\'s campaign headquarters, later engulfed President Richard M. Nixon and many of his supporters in a variety of illegal acts, and culminated in the first resignation of a U.S. president. The burglary was committed on June 17, 1972, by five men who were caught in the offices of the Democratic National Committee at the Watergate apartment and office complex in Was
Hypoglycemia Hypoglycemia About four years ago we started to notice that my dad was having problems sleeping, he was very moody, and he started getting headaches a lot. After it got to a point where my dad was feeling bad every day we all started to worry. So as any normal person would do, my dad went to the hospital to have it checked out. The doctor found that my dad had developed a disease called hypoglycemia. At first this was very hard for my dad to handle because to subdue the symptoms of
Influence of inFLUenza December 8, 1998 Microbiology 3300 9:00-11:50 Case Study: "The InFLUence of the Influenza" The patient Terry B. (Case no.19), has acquired the microbial agent Pneumonia Influenza. The patient is a three year old white male with a headache, lethargy and was running a high fever of 39.7 degrees Celsius. He has suffered from a previous illness of infection of the upper respiratory. Due to the fever, he had a systolic of 110 over 75 diastolic; pulse of racy 100. The fever also
Multiple Sclerosis A Research Paper Introduction Multiple Sclerosis By: Stephanie **** Multiple Sclerosis (MS) is a chronic, often disabling disease that randomly attacks the central nervous system (brain and spinal cord). The progress, severity and specific symptoms of the disease can not be predicted; symptoms may range from tingling and numbness to paralysis and blindness. MS is a devastating disease because people live with its unpredictable physical and emotional effects for the rest of the
Animal Rights Vs Human Rights „h Laboratory animals The use of laboratory animals is important to three main areas: biomedical research, product safety testing, and education. Biomedical researchers use animals to extend their understanding of the workings of the body and the processes of disease and health, and to develop new vaccines and treatments for various diseases. The research these people do isn¡¦t only for human benefit; it is also helping to develop veterinary techniques. The industry
Parasitic wasps Introduction Malaria is one of the most prevalent and dangerous diseases known to man. It has existed for centuries and affects a myriad of people in the tropical region. Even today, with our newly discovered treatments for many of the tropical diseases, over 10% of the people that are infected with malaria each year and do not receive proper treatment die. In Africa alone, over 1 million children die each year because of malaria and new cases are reported frequently. Malaria is
Spiders Spiders This report deals with testing the toxicity of certain chemicals on spiders, and determining the toxicity by how it affects it’s ability to weave it’s web. This report contains research on the four chemicals (benzedrine, chloral hydrate, caffeine, and alcohol) as wellas the spiders and their webs. Spiders are of course found in the class Arachnidia, which also contain mites, scorpions, and other arthropods. The order which spiders are classified under is called Araneae, a word of
The International Space Station The International Space Station is the doorway to the future of mankind and the world as it is known. The scientific and medical discoveries that will be made on the station could create billions of dollars annually. A plan like this, arranged to benefit the whole world economy, should sound like a good idea to every person, but some believe that the ISS is too risky, too ineffective, or too costly to create. Whether or not the space station is worth the money, ti
Billy Graham "This is the Hour of Decision with Billy Graham, coming to you from Minneapolis Minnesota" Billy Graham, has preached to more than 210 million people through a live audience, more than anyone else in history. Not only that, but Mr. Graham has reached millions more through live televison, video and film. This has led Billy to be on the "Ten Most Admired Men in the World" from the Gallup Poll since 1955 a total of thirty-nine times. This includes thirty-two consecutive more than any o
Vlad Tepes Many people know of Dracula from the movie or novel of Bram Stoker’s Dracula, and are aware that there is was a true historical Dracula. Bram Stoker penned his immortal classic, "Dracula", he based his vampire villain on a Romanian historical figure. Stoker\'s model was Vlad III Dracula ( Tepes - The Impaler), a fifteenth century viovode of Wallachia of the princely House of Basarab. Wallachia (Tara Romaneasca) is a provence of Romania bordered to the north by Transylvania and Moldavi
MARIJUANA The Controversial Drug DESCRIPTION: Marijuana is a green, brown, or gray mixture of dried, shredded flowers and leaves of the hemp plant, Cannabis sativa. Marijuana is often called by street names such as pot, herb, weed, boom, Mary Jane, gangster, reefer, or chronic. There are more than 200 slang terms for marijuana. HISTORY: Cannabis was acknowledged as early as 2,700 BC in Chinese manuscripts. Marijuana has been used as a medicine throughout the world since the beginning of written
Animal House Social commentary is sometimes found at the heart of good art, whether that art form is literature or popular music. The novel, Animal Farm by George Orwell, and the rock album, Animals written and performed by Pink Floyd share the same characteristic of scathing social commentary. The artworks also share an animal metaphor that serves to cast a dark light on human social interactions and stratification functions. Conversely, the artworks individually attack the diametrically oppose
world hunger World Hunger Every day an estimated 24,000 people die from hunger or hunger related causes. Three-fourths of these deaths are children under the age of five. One may wonder how this can be living in a country were it seems so much food is wasted everyday. Food restaurants and grocery stores throw away food every night before closing. Many Americans waste food every day within their own homes. With so much left over food in American how is it that an estimated 800 million people ar
Managing People with AIDS Today, AIDS is the second leading cause of death among adults between the ages of 25 and 44. With more than half of the nation’s 126 million workers in this age group, managers cannot afford to ignore this deadly disease. As more effective drug therapies, such as protease inhibitors, are extending the lives of HIV positive people, an increased number are able to return to the workforce and stay productive. One in six large companies has had an employee with HIV/AIDS and
Supply and Demand Recent medical advances have greatly enhanced the ability to successfully transplant organs and tissue. Forty-five years ago the first successful kidney transplant was performed in the United States, followed twenty years later by the first heart transplant. Statistics from the United Network for Organ Sharing (ONOS) indicate that in 1998 a total of 20,961 transplants were performed in the United States. Although the number of transplants has risen sharply in recent years, the
computer hackers REACTION PAPER FOR CASE STUDY #2, Chapter 17 This Reaction Paper represents my comments about and answers to questions concerning Case Study #2 in Chapter 17, pages 531 and 532 of the textbook. The comments and answers represent my interpretation of what the Case Study is about. Question 1. Sometimes, a successful break-in into system makes it easy to invade many other systems. Answer. Some systems include information that helps hackers invade other systems. Some systems hold su
Dna Computing The Future or the End DNA Computing, The Future or the End? The future of computers is in the hands of the next century. The evolution of the Computer Age has become a part of everyday life, and as time proceeds, people are depending more and more on computer technology. From controlling a small wrist watch to the largest super-computers that can calculated the center of the universe, computers are essential for everyone in modern societies. Even most societies outside of the civil
The wave of the future The wave of the future is drowning out very quickly. All the technology we have created will bit the dust before the systems really are used. At the end of the century all systems that have calendars to monitor systems or use calendars to show dates will shut down all at once. Major electronic systems such as elevators, alarm systems, fax machines, telephones, cars with computer systems will be nothing more than paper weights or wall designs nothing more. For years compute
the year 2000 bug Do you have a home computer or a small business with a computer? You have undoubtedly read or heard information about the upcoming new century and are wondering if you need to do something to help your PC make the transition into the year 2000. This site is constructed to help you answer that question, and to help you sort fact from fiction. The way that your computer system will be affected by the year 2000 will depend not only on the equipment and software that you have, but
Legalization of Marijuana How can something so good be so bad??? There is a large drug problem facing Canada today, and this problem extends to all citizens. It’s not just the poor and the uneducated that are affected by this problem. The most largely used illegal drug in Canada is Marijuana, and thus is targeted as the drug for law enforcement to target the most, costing the taxpayers lots and lots of money. I will show you that Marijuana is not as large an evil as it may appear, and that if le
Say No to Marijuana Legalization Say No to Marijuana Legalization Marijuana also known as cannabis sativa is being used illegally by many Americans today of all ages. Before the 1960s, many Americans had never heard of marijuana, but today it is the most used illegal drug in this country. All types of marijuana are mind-altering drugs. They all contain THC, the main active chemical in marijuana, along with over 400 other chemicals. This drug should stay illegal for many reasons concerning the he
drug abuse with athletes Drugs and Athletes Drugs have been a problem in our society for many years. They have been used and abused by many groups, including professional athletes. It is certainly quite common to hear about or read about athletes and drug use. Although drugs have a lengthy history of use by athletes, they have varied effects on the body and different preventions. Much of the world\'s supply of cocaine is produced in South America. Thousands of years ago, the ancient Incas of Per
Genetic Engineering Genetic Engineering: A leap in to the future or a leap towards destruction? Introduction Science is a creature that continues to evolve at a much higher rate than the beings that gave it birth. The transformation time from tree-shrew, to ape, to human far exceeds the time from an analytical engine, to a calculator, to a computer. However, science, in the past, has always remained distant. It has allowed for advances in production, transportation, and even entertainment, but n
A book report on A Voyager Out Frank, Katherine. A Voyager Out: The Life of Mary Kingsley. Boston: Houghton Mifflin Company. 1986 Katherine Frank’s novel A Voyager Out tells the life story of Mary Kingsley. She talks of her childhood, her young adult life, and her traveling life. She wanted to tell the world what this woman explorer did for Africa. Mary Kingsley had a famous family, many of whom were writers. Mary herself wrote two books. In her books however, she leaves out a lot about her life
Aids and Society Brenden English Aids and Society The number of newborns infected by vertical transmission of the human immunodeficiency virus is increasing as the number of HIV-positive women increases within the United States. It is estimated that while seven thousand of the HIV-positive women become pregnant each year, between one thousand and two thousand of their newborns will be HIV-positive. The transmission of the human immunodeficiency virus from mother to child, the benefits of drugs i
CancerIs there an effective treatment Introduction Purpose One of the many complications with cancer is that there are so many different types. Currently, there are 112 types of cancer, and there is an estimated 80 more types of cancer that are undiscovered. (United States Cancer Rates…) That leads to as many different treatments as there are types of cancer. Figure 1, located after the Recommendations section, on page 8 displays the number of recorded cancer cases over the past 15 years. I prop
EVENGE AND LOVE THEME IN WUTHEING HEIGHTS BY EMILY BRONTE Explore the writers oppression in Nineteen Eighty Four and Brave New World Both Orwell and Huxley present to the reader in their novels Brave New World and Nineteen Eighty Four, a new society, one reinvented where totalitarian aspects of society rule. Both societies strive for stability and inevitably a utopian society. Orwell and Huxley explore the possibilities of achieving this, and warn of the dangers and impracticability of attemptin
Creationism VS Evolution Evolution is not only improbable but clearly impossible. Extensive evidence against evolution is uncovered with every major scientific discovery. Every evolutionist "fact" can easily be rebuked by creationists. Twelve supposed hominoids have been discovered and presented as supporting evidence to evolution. While in all actuality nine of the twelve supposed hominids are actually extinct species of ape. While the remaining three are completely developed humans. Neandertha
current problems in antarctica CURRENT EVENTS of antarctica Global Warming If all the ice in Antarctica melted, it would raise the level of the world\'s oceans by over 200 feet (60 meters). The possibility of this happening in the near term is not seriously considered by scientists, for the Antarctic icecap is currently believed to be in equilibrium. However, meteorologists studying the ramifications of global warming and the greenhouse effect expect there to be a decrease in sea levels in the s
environmental hazadous ENVIRONMENT: Every thing present in this universe is a part of environment including ourselves. Whether they are animals , living thing, or nonliving things. All of the external factors affecting an organism. These factors may be other living organisms (biotic factors) or nonliving variables (abiotic factors), such as water, soil, climate, light, and oxygen. All interacting biotic and abiotic factors together make up an ecosystem. Organisms and their environment constantly
Insecticides An insecticide is used to kill insects. There are many kinds of insecticides, but organic insecticides are the most commonly used (World Book, 1999). Organic insecticides are split into three different categories: Chlorinated hydrocarbon insecticides, organophosphate insecticides, and carbamate insecticides (World Book, 1999). In this paper, I\'ll explore how toxic each of these insecticides are, how they affect wildlife, humans, and the environment, and what we can do to help. WHY
ocean water Outline 1. Introduction to open water waste disposal. 2. Introduction of oil into marine environments. 1. Effects upon environment. 2. Effects upon living organisms. 3. Introduction of plastics/pollutants into marine environments. 1. Effects upon living organisms. 4. Possible solutions to waste disposal into our water systems. 1. Military applications. 2. Research and developments. 5. Conclusion The oceans and the life they sustain have had enough. They can no longer endure the unwan
The Hudson River and PCB Pollution The Hudson River and PCB Pollution The Hudson River is a body of water that stretches for 315 miles from the Adirondack Mountains to the Battery in Manhattan, reaching its deepest point of 216 feet in the Highlands near Constitution Island and West Point and reaches its widest point of 3 miles across at Havestraw. This river is one of the most beautiful and scenic of the Tri-State area. Unfortunately, it happens to be New York’s most polluted river. The river h
Ethics of Cloning Running head: Downside of Cloning The Ethical Downside of Cloning Ethics in Health Care October 17, 1998 Introduction For the first time the cloning of a whole human being seems really possible. It is absolutely necessary to consider the harm that can be done and move to curb abuses. Also, it is important to understand some of the theory underlying the desire to build a better human. The Ethical Downside of Cloning With recent developments in the cloning of the first whole mamm
Colonialization in Africa Each country in the entire world has experienced a great deal of change whether it be Religion, beliefs, food, or education. You may think that just because you live in the United States that every state has evolved the same, well not really at all the East coast was all founded years before the West and just like America other countries follow a similar pattern like Africa. There are so many different African countries that all have such different pasts and different s
Colonialization in Africa1 Each country in the entire world has experienced a great deal of change whether it be Religion, beliefs, food, or education. You may think that just because you live in the United States that every state has evolved the same, well not really at all the East coast was all founded years before the West and just like America other countries follow a similar pattern like Africa. There are so many different African countries that all have such different pasts and different
TCE What is TCE? TCE is a nonflammable liquid it is colorless. It has a sweet odor and a sweet burning taste. TCE does not occur naturally in the environment. It is an artificial compound. It is produced synthetically from 1,2-dichloroethane. And stabilizers are added to the marketed product. What is TCE used for? It is used mainly as a solvent to remove greases from metal parts, it is also an ingredient in adhesives, typewriter correction fluid and spot and paint removers. 75-80% of TCE product
Thailand1 IINTRODUCTION Thailand, formerly Siam, officially Kingdom of Thailand, kingdom in Southeast Asia, bounded by Myanmar (formerly known as Burma) on the north and west, by Laos on the northeast, by Cambodia and the Gulf of Thailand (Siam) on the southeast, by Malaysia on the south, and by the Andaman Sea and Myanmar on the southwest. The total area of Thailand is 513,115 sq km (198,115 sq mi). Bangkok is the capital and largest city. IILAND AND RESOURCES Thailand lies within the Indochine
Aids 12 00 AIDS By: Albert Alarcon Health 23 Introduction: AIDS is a life and death issue. To have the AIDS disease is at present a sentence of slow but inevitable death. I\'ve already lost one friend to AIDS. I may soon lose others. My own sexual behavior and that of many of my friends has been profoundly altered by it. In my part of the country, one man in 10 may already be carrying the AIDS virus. While the figures may currently be less in much of the rest of the country, this is changing rap
AIDS A US Made Monster misc 12 00 PREFACE In an extensive article in the Summer-Autumn 1990 issue of "Top Secret", Prof J. Segal and Dr. L. Segal outline their theory that AIDS is a man-made disease, originating at Pentagon bacteriological warfare labs at Fort Detrick, Maryland. "Top Secret" is the international edition of the German magazine Geheim and is considered by many to be a sister publication to the American Covert Action Information Bulletin (CAIB). In fact, Top Secret carries the Nami
AIDS and HIV misc 12 00 Jonathan N. Dukes December 1, 1999 Health / 6th Period Ms. J Thesis: The AIDS and HIV viruses are getting worse in the United States and the rest of the world. Introduction Although more people die of heart disease and cancer each year, AIDS has become the health problem people fear the most. Much of the fear comes from ignorance and misunderstanding. Education is the most effective tool against AIDS. It is more important than ever for young people to learn the facts abou
AIDS And ou misc 12 00 Introduction: AIDS is a life and death issue. To have the AIDS disease is at present a sentence of slow but inevitable death. I\'ve already lost one friend to AIDS. I may soon lose others. My own sexual behavior and that of many of my friends has been profoundly altered by it. In my part of the country, one man in 10 may already be carrying the AIDS virus. While the figures may currently be less in much of the rest of the country, this is changing rapidly. There currently
AIDS AS AN INVADER misc 12 00 Acquired immune deficiency syndrome, also known as AIDS, is a silent invader. The first cases of this disease were reported in the early 1980’s. AIDS is caused by the infection known as human immunodeficiency virus (HIV), which is a microscopic organism that can grow and multiply inside living cells. HIV attacks and disables the body’s immune system. The immune system is the system that usually fights off illnesses. “When the immune system breaks down, a person with
Aids in Africa misc 12 00 AIDS In Africa: A Rising Problem Africa is a continent with many social issues and problems. These social issues range from overpopulation, racism, and a countless number of disease epidemics. One of the most deadly and uncontrollable of these diseases is the HIV virus, or AIDS. AIDS is an illness that involves several phases. It is caused by a virus that can be passed from person to person. AIDS impairs the human body\'s immune system the system responsible for warding
aids misc 12 00 l Can\'t find it here? Try Collegiate Care AIDS By: Gilbert Gonzales Gonzales 1 The Acquired Immune Deficiency Syndrome (AIDS) was first discovered in 1981 as a unique and newly recognized infection of the bodys immune system (Mellors 3). The name AIDS was formally know as GRIDS (Gay Related Immune Defiance Syndrome). The first case of AIDS was discovered in Los Angeles, where scientists from the CDC (Center for Disease Control) were called in on a half dozen cases. The CDC was
aids1 misc 12 00 l The purpose of this paper will be too show how AIDS is a serious disease in the world today. AIDS, (Acquired Immune Deficiency Syndrome) is a complicated illness, caused by a virus that is passed from person to person. "The disease was first recognized in 1980 among homosexual men and injection drug users in New York and California." Several years after it was recognized, AIDS has become a worldwide epidemic. "By 1995, 477,900 Americans had developed the disease, of whom 295,5
Alternative Medicine Chiropractic Adrian Arbuckle Professor Gibbons English 1302-8456 25 May 2000 Alternative Medicine: Chiropractic Chiropractic is the third largest doctoral-level health profession in the United States, after medicine and dentistry. This form of health care is on the rise and there are more than forty thousand chiropractors in practice in all fifty states, the District of Columbia, and many other nations. Chiropractic is a form of alternative medicine commonly used and accepte
Arthritis What Is Osteoarthritis? Osteoarthritis is a disease that causes the cartilage in your joints to break down. Cartilage is a smooth substance that protects the ends of your bones and helps your joints move. Osteoarthritis becomes more common as people get older. To diagnose this disease, your doctor will ask about your and your families’ health history. X-rays and an exam may also be needed. Symptoms Osteoarthritis can affect any joint. Weight-bearing joints, such as the hip and knee, ar
Breast Impants Breast Implants I. Should breast implants be concidered dangerous or are they safe for women to use? Small-breasted women in America say that they feel inferior or unfeminine in a culture where breast size is a major issue. Popular fashion models today are usually thin,but large-breasted,especially those who model lingerie,evening wear and swimsuits. With American culture seeming to equate cleavage with sexiness,it is no wonder that some smaller-breasted women doubt their attracti