Bios 255 Exam 3 Questions and Answers

Bios 255 Exam 3 Questions and Answers red bone marrow and thymus What are the primary lymphatic organs? lymph nodes, tonsils, spleen What are the secondary lymphatic organs? 15% of interstitial fluid that has been absorbed by the lymphatic vessels What is lymph? A pump such as the heart What do lymphatic vessels lack? Stretching of the vessels to open valves that allow one directional flow for lymph What do lymphatic vessels rely on? from blood that is forced out of capillaries and is not reabsorbed Where does lymph come from? macrophages, hormones, bacteria, viruses, cellular debris, cancer cells What does lymph contain? Skeletal muscle pumps Lymphatic flow can also be produced by what? When certain cells (especially leukocytes) are infected with viruses, they secrete interferon proteins What are interferons? alert neighboring cells and protect them from becoming infected What do interferons do? Surface receptors on infected cells and activate second-messenger systems within What do interferons bind to? NK cells and macrophages What do interferons activate? Destroy infected cells before they can liberate a swarm of newly replicated viruses. What do NK cells and macrophages do? A group of 30 or more globular proteins that make up powerful contributions to both innate and adaptive immunity What is the complement system? It completes the action of an antibody Why is is named "complement" system? the liver Where are complement proteins mainly synthesized by? Circulate in the blood in inactive form and are activated in the presence of pathogens What do complement proteins do? inflammation, immune clearance, phagocytosis, cytolysis Activated complement contributes to pathogen destruction by what methods? A local defense response to tissue injury of any kind, including trauma and infection What is inflammation? limiting the spread of pathogens and destroying them, remove debris from damaged tissue, and initiate tissue repair What is the general purpose of inflammation? Redness, swelling, heat, pain What are the 4 cardinal signs of inflammation? Any molecule that triggers an immune response What are antigens? Venoms, toxins, food molecules, component of bacterial cell membranes, and viruses What are examples that can trigger antigens? Small regions of a large antigen molecule that stimulate immune responses What are epitopes? To small to be antigenic in themselves What are haptens? can trigger an immune response by combining with a host macromolecule and creating a complex that the body recognizes as foreign What can haptens do? cosmetics, detergents, industrial chemicals, poison ivy, animal dander, and penicillin Examples of haptens? Employs antibodies that do not directly destroy a pathogen, but marks it for destruction What is humoral immunity? extracellular viruses, bacteria, yeast, protozoans, toxins, venoms, and allergens What is humoral immunity effective against? Plasma cells (B lymphocytes) Humoral immunity antibodies are produce by what? Plasma cells, b cells, and helper t cells What cells are involved with humoral immunity? Prevents pathogens from adhering to epithelia and penetrating underlying tissues. Provides passive immunity to the newborn IgA antibody Activates B cells by antigens IgD antibody Stimulates cells to release histamine and other mediators of inflammation and allergy, important in immediate hypersensitivity reactions IgE antibody Secondary immune response, complement-fixation activity. Crosses placenta and confers temporary immunity on the fetus IgG antibody Part of the antigen receptor, occurs in blood, plasma, and lymph. Primary immune response, very strong agglutinating and complement-fixation abilities IgM antibody T cells develop surface antigen receptors and are capable of recognizing antigens presented to them (immunocompetent) What is positive selection of T cells? T cells must not react to self-antigens presented to them, develop self-tolerance What is negative selection of T cells? 2% What percent of T cells "graduate" from the thymus? They wait to encounter an antigen, they are ready to be "activated" to "fight" When T cells migrate to secondary lymphatic organs and tissues what happens? Red bone marrow where do B cells become immunocompetent? Bone marrow B cells go through the same process as T cells but in which location? Synthesize antigen surface receptors, divide rapidly and produce immunocompetent clones What do self-tolerant B cells do? vaccination exposes a person to a specially prepared microbial stimulus, in a form that does not cause the disease. This then triggers the immune system to produce antibodies and lymphocytes to protect the person upon future exposure to that microbe. The degree and length of protection vary. Describe the immune system response when you are vaccinated Factors that affect oxygen unloading from hemoglobin are CO2, PO2, PH, and temp. In active tissue CO2 increases because the muscles are using more ATP, the temperature increases, the PH goes down because active muscles release lactic acid, and the PO2 decreases because the muscles need more oxygen for ATP. Describe factors that affect oxygen unloading from hemoglobin. How are the factors different in active tissues? PO2, CO2, PH, temp What are the factors that affect oxygen unloading from hemoglobin? PO2 decreases, CO2 increases, PH decreases, temp increases How do factors change in active tissues? When you inhale, the diaphragm contracts and pulls down which increases the thoracic volume. This decreases the intrapulmonary pressure, and the atmospheric pressure is greater. So air flows in the lungs. When you exhale the diaphragm relaxes and pushes up which decreases the thoracic cavity volume. This increases the intrapulmonary pressure and the atmospheric pressure is lower so air flows out of the lungs.43q Explain how pressure gradients cause the flow of air into and out of the lungs. How are the pressure gradients created? When you exhale the diaphragm relaxes and pushes up: the thoracic volume decreases and the intrapulmonary pressure increases During exhalation what happens to the thoracic volume and intrapulmonary pressure? When you inhale the diaphragm contracts and pulls down: increasing thoracic volume and decreasing intrapulmonary pressure During inhalation what happens to the thoracic volume and intrapulmonary pressure? To the right Does the decrease in pH (increase in hydrogen) shift the curve to the left or right? To the left Does an increase in pH (decrease in hydrogen) shift the curve to the left or right? At the level of the lungs (alveoli) exchange of gases External respiration At the level of the rest of the body exchange of gases Internal respiration one cycle of inhalation whereby air is moved into the lungs, and one cycle of exhalation whereby air is expelled from the lungs Respiratory cycle Breathing (inhaling and exhaling) Ventilation inhaling Inspiration exhaling Expiration Gas diffuses down their own gradients until the partial pressure of each gas in the air is equal to its partial pressure in the blood What happens during alveolar gas exchange? The process of carrying gases from the alveoli to the systemic tissues and vice versa What happens during gas transport? 98.5% bound to hemoglobin 1.5% dissolved in plasma Oxygen transport 70% of CO2 becomes carbonic acid/bicarbonate ions 23% bound to proteins (hemoglobin) 7% dissolved in plasma Carbon dioxide transport Total atmospheric pressure is the sum of the contributions of the individual gases dalton's law the separate contribution of each gas in a mixture Partial pressure PO2 = 40 mmHg PCO2 = 46 mmHg Partial pressure of O2 and CO2 in deoxygenated blood PO2 = 95 mmHg PCO2 = 40 mmHg Partial pressure in oxygenated blood The amount of air inhaled and exhaled in one cycle during quiet breathing Tidal volume The amount of air in excess of tidal volume that can be inhaled with maximum effort Inspiratory reserve volume Amount of air in excess of tidal volume that can be exhaled with maximum effort Expiratory reserve volume Amount of air remaining in the lungs after maximum expiration. The amount that can never be voluntarily exhaled Residual volume The amount of air that can be inhaled and then exhaled with maximum effort. The deepest possible breath. (VC = ERV + TV + IRV) Vital capacity The maximum amount of air that can be inhaled after a normal tidal expiration (IC = TV + IRV) Inspiratory capacity Amount of air remaining in the lungs after a normal tidal expiration (FRC = RV + ERV) Functional residual capacity Maximum amount of air the lungs can contain (TLC = RV + VC) Total lung capacity Multiply tidal volume by respiratory rate Ex. person has tidal volume of 500 mi per breath and 12 breaths per minute 500 x 12 = 6000 mi/min or 6L/min Calculating minute respiratory volume (MRV) Diaphragm flattens out, making thoracic cavity larger Quiet inspiration Pulls ribs up and out elevating sternum External intercostals Erector spinae, sternocleidomastoid, pectoralis major, pectoralis minor, serratus anterior, and scalenes Forceful inspiration Relaxation of diaphragm return to smaller size Quiet expiration Internal intercostals and abdominal muscles contract Forced expiration