Test 2 extended responses Flashcards
- A. Define the immune system. (2 pt.) B. What are the primary immune cells called, their function, and origin (include 2 subdivisions)? (3 pts.)
A. The immune system is an ordered system of cells, hormones, and chemicals that regulate susceptibility, severity, and recovery from infection and illness.
B. leukocytes.
In the immune system the leukocytes protect the body against infectious diseases and foreign is invaders.
All white blood cells are produced and derived from multipotent cells in the bone marrow known as hematopoietic stem cells.
The subdivision of leukocytes are lymphocytes and phagocytes.
- A. Define inflammation. (2 pts.) B. List the four processes involved in the inflammatory response. (3 pts.)
A. Inflammation is the bodily response to an injury, infection, or antigen that prevents the spread of damaging agents by disposing of pathogens and cellular debris; and sets the stage for tissue repair.
B.The four processes involved in the inflammatory response are
- — 1) vasodilation of blood vessels with the release of histamine to increase blood flow to the bacterial infected area,
- —-2) increased capillary permeability to allow for blood clotting elements (platelets and thrombin),
- —-3) migration of leukocytes and macrophages to the site of the infection known as chemotaxis,
- —-4). Serum proteins along with phagocytic leukocytes destroy bacteria (neutrophils-form puss) and clean up cell debris (monocytes).I️
- List and explain three guidelines for helping the immune response system during physical activity or in the winter season. (4 pts.)
- Eat a well-balanced diet. Improper nutrition can compound the negative influence of heavy exertion on the stress immune response system. Cortisol suppresses the immune system and inflammatory pathways, rendering the body more susceptible to disease.
- Avoid excessive muscular soreness. Muscle soreness requires immune system involvement. The leukocytes known as T-cells,the immunesystem responders are present in yoursore musclesfollowing exercise and may decrease your ability to fight off viruses.
- Get a flu vaccination. These antibodies provide protection against infection with the weakened influenza viruses that are in thevaccine. Flu shots are especially important for the winter season, because cold temperatures lead to drier air, which may dehydratemucous membranes, preventing the body from effectively defending against respiratory virus infections.
Explain the 1st stage of HIV?
Stage 1 Acute HIV infection is the earliest stage of HIV infection, and it generally developswithin 2 to 4 weeks after a person is infected with HIV.The initial infection can feel like the flu with such symptoms as a fever, headache, and rash. In the acute stage of infection, HIV multiplies rapidly and spreads throughout the body. The virus attacks and destroys the infection-fightingCD4 cellsof the immune system. During the acute HIV infection stage, the level of HIV in the blood is very high, which greatly increases the risk of HIV transmission.
Explain the 2nd stage of HIV?
Stage 2 The second stage of HIV infection is chronic HIV infection (alsocalled asymptomatic HIV infection or clinical latency). An asymptomaticcarrier(healthy carrier) is a person that has contracted an infectious disease, but who displays no symptoms. Although unaffected by the disease themselves,carrierscan transmit it to others. During this stage of the disease, HIV continues to multiply in the body but at very low levels. People with chronic HIV infectionmay not have any HIV-related symptoms, but they can still spread HIV to others. Without treatment with HIV medicines (Ziagen, Epivir) chronic HIV infection usually advances to AIDS in10 years or longer, though it may take less time for some people.
Explain the 3rd stage of HIV?
Stage 3 AIDS is the final, most severestage of HIV infection. Because HIV has severely damaged the immune system, the body can’t fight offopportunistic infections. (Opportunistic infections are infections and infection-related cancers that occur more frequently or are more severe in people with weakened immune systems than in people with healthy immune systems.) People with HIV are diagnosed with AIDS if they have a CD4 count of less than 200 cells/mm3or if they have certain opportunistic infections. Without treatment, people with AIDS typically survive about 3 years.
- A. What is AIDS? (2 pts.) B. List three guidelines for physical activity with an AIDS patient. (3 pts.)
A. Acquired Immune Deficiency Syndrome: Acquired means you can get infected with it; Immune Deficiency means a weakness in the body’s system that fights diseases; Syndrome means a group of health problems that make up the disease. AIDS is a disease caused by the human immunodeficiency virus (HIV) and is characterized by a severe loss of the body’s cellular immunity or T-cell count, greatly lowering the resistance to infection and malignancy. It is characterized by a severe T-cell (CD 4marked protein) or T-helper cell depletion of 200 or below.
- what are the Three guidelines for physical activity with a patient with AIDS are as follows:
- Remain physically active. During exercise, leukocytes are recruited to the peripheral blood, resulting in increased concentrations of neutrophils, lymphocytes and monocytes. The increased lymphocyte concentration is caused by recruitment of all lymphocyte subsets (NK, T and B cells).
- Participate in moderate exercise. CD4 cell counts of AIDS/HIV infected persons who participated in moderate intensity aerobic exercise (treadmill) significantly improved. However, strenuous exercise is followed by decreased concentrations of lymphocytes and decreases the percentage of T cellsin blood circulation thus should be avoided.
- Proper exercise stress training on a symptom-limited basis, and adherence to antiretroviral therapy may enhance immune function in HIV population. Used to evaluate heart function, a symptom-limited exercisestress testrequires that a patient exercises on a treadmill or exercise bicycle while his or her heart rate, breathing, blood pressure, electrocardiogram (ECG), and feeling of well-being are monitored.Antiretroviraltherapy(ART) is treatment of people infected with human immunodeficiency virus (HIV) using anti-HIV drugs such as abacavir (Ziagen), lamivudine (Epzicom), zidovudine (Retrovir). The standard treatment consists of a combination of at least three drugs (often called “highly active antiretroviral therapy” orHAART) that suppress HIV replication (the RNA genetic coding in DNA is stopped).
- Explain the 6 essential activities of the digestive system in processing food. (6 pts.)
1) Ingestion- taking food into the digestive tract via the mouth.
2) Propulsion- moving food through the alimentary canal by swallowing and peristalsis (Peristalsis is waves of contraction and relaxation of muscles in the organ walls that propel contents from one point to another).
3) Mechanical digestion- physically prepares food for chemical digestion by enzymes. Chewing, mixing of food with saliva by the tongue, churning food in the stomach, and segmentation or intestine constrictions that mixes food with digestive juices to increase absorption efficiency.
4) Chemical digestion- catabolic breakdown of food to their building blocks; accomplished by enzymatic breakdown of food in the mouth and completed in the small intestine.
5) Absorption- movement of nutrients (vitamins, minerals, and water) from the GI tract to the blood or lymph. The small intestine is the major absorptive site of mucosal cells.
6) Defection- elimination of indigestible solid wastes from the body via the anus in the form of feces.
- Describe 5 major functions of the stomach. (5 pts).
1) The stomach performs mechanical digestion with peristaltic waves mixing food with gastric juice and propelling it into the duodenum (propulsion).
2) The stomach serves as a storage site for food degrading it with hydrochloric acid and secreting intrinsic factor required for absorption of vitamin B12 (parietal cells release both acid & factor).
3) The stomach enzymatically digests proteins with pepsin (chief cells release pepsinogen).Enteroendocrine cells release regulatory hormones, serotonin and histamine to trigger cells to regulate HCL acid and contract smooth muscle tissue of the stomach. Somatostatin is released to inhibit secretions. G cells produce the hormone, gastrin which stimulates gastric and muscle activity of the stomach.
4) The stomach delivers chyme (partly digested food) through the ileocecal valve to the small intestine.
5) The stomach absorbs fat-soluble substances such as alcohol and aspirin, water, and salt.
- Give a detailed description of the small intestine (include structural anatomy, function, enzymes, mechanical, chemical, and absorption, etc.). (8 pts.)
The small intestine is the major place for digestion and absorption. The structural anatomy of the small intestine consists of the duodenum, jejunum, and ileum. The circular folds, villi (finger-like protrusions inside small intestine), and microvilli (same as villi but on the surface of a single absorptive cell) of the small intestine increase the surface area for the absorption of food. The small intestine continually mixes food with digestive juices and moves it along the digestive tract through the ileocecal valve at a slow rate, allowing sufficient time for digestion. The breakdown of carbohydrate, protein, and nucleic acid digestion occurs in the small intestine. Alkaline mucus produced by intestinal glands and bicarbonate-rich juice ducted in from the pancreas help neutralize the acidic chyme and HCl from the stomach. This neutralization facilitates digestive enzymes in the small intestine including protease and amylase and pancreas enzymes (pancreatic amylase for carb breakdown) to complete food digestion which would be denatured by the stomach acidity. The final step in digestion of dietary carbohydrates and proteins occurs on the face of small intestinal enterocytes (cells of the intestinal lining). Brush border enzymes such as aminopeptidase, attached to the villi membranes, will carry the resulting sugars and amino acids into the epithelial cells of the GI tract. Each villus has a network ofcapillariesand fine lymphatic vessels called lacteals close to its surface. The epithelial cells of the villi transport nutrients from the lumen (internal space) of theintestineinto thesecapillaries(amino acids and carbohydrates) and lacteals (lymphatic capillary that absorbs dietary fats). Bile (stored in gall bladder) produced by the liver emulsifies fats and enhances fatty acid and fat-soluble vitamin absorption with the enzyme lipase.
