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EK Bio 7
cardiovascular system, respiratory system
| Question | Answer |
|---|---|
| path of blood in heart | left ventricle - aorta - arteries - arterioles - capillaries - venules - veins - superior/inferior vena cava - R atrium - tricuspid valve - R ventricle - pulmonary valve - pulmonary artery - lungs - pulmonary vein - L atrium - mitral valve - L ventricle |
| what contracts during systole? | ventricle |
| what contracts during diastole? | atria |
| transmission of cardiac impulse | SA node autocontracts spreading via electrical synapses to atria (then atria contract) then to AV node down to the bundle of His to Purkinje fibers |
| SA node | sinoatrial node, grp of specialized cardiac muscle cells, innervated by vagus nerve (slows pace of SA node bc pace is faster than normal heartbeats) |
| characteristics of arteries | elastic, stretch when filling w/ blood, recoil after ventricle contraction, wrapped in smooth muscle |
| epinephrine role on blood vessels | powerful vasoconstrictor |
| characteristics of arterioles | smaller than arteries and wrapped in smooth muscle, this makes the constriction and dilation of arterioles important for regulating BP and rerouting blood |
| larger arteries have more or less smooth muscle per volume than medium arteries... which will have what effect? | less smooth muscle per volume which means then are less affected by sympathetic stimulation |
| characteristics of capillaries | microscopic blood vessels, walls are only 1 cell thick, diameter = diameter of 1 RBC, where nutrient and gas exchange occurs w/ any tissue |
| 4 methods for materials to cross capillary walls | pinocytosis, diffusion/transport thru capillary cell membranes, movement thru pores in cells (fenestrations), movement thru space btw cells |
| as blood flows into a capillary, hydrostatic pressure is (greater/smaller) than osmotic pressure, and net fluid flow is (in/out) of the capillary | hydrostatic pressure is greater than osmotic and net fluid flow is out of the capillary and into interstitum |
| osmotic pressure in capillaries | usually remain relatively constant throughout |
| venule end of capillary has (greater/smaller) hydrostatic pressure compared to osmotic pressure? | smaller, so osmotic pressure overcomes hydrostatic pressure and net fluid flow is into capillary and out of interstitium |
| net result of fluid exchange by capillaries is how much loss of fluid into interstitium? | 10% |
| veins, venules, and venus sinuses in systemic circulation hold how much % of blood in body at rest? | 64% |
| arteries, arterioles, and capillaries in systemic circulation hold how much % of blood at rest? | 20% |
| how do the cross sectional areas of veins and arteries compare? | area of veins are 4 times that of arteries |
| blood moves the slowest in the... | capillaries |
| how does blood pressure compare in the systemic blood vessels? | increases near the heart (aorta) and decreases to its lowest in capillaries/veins; valves are needed in veins to prevent backflow |
| pathway of airflow in respiratory system? | nose - pharynx - larynx - trachea - bronchi - bronchioles - alveoli |
| what signals the diaphragm to contract? | medulla oblongata of the midbrain |
| what is the diaphragm? | skeletal muscle innervated by the prenic nerve; when relzed, it is dome shaped and flattens upon contraction to expand chest cavity and create negative gauge pressure |
| nasal cavity | space inside the nose; filters, moistens, and warms incoming air |
| pharynx | aka throat; functions as a pathway for food and air |
| larynx | voice box, sits behind epiglottis |
| epiglottis | cartilaginous member that prevents food from entering trachea during swallowing |
| trachea | aka windpipe, lies in front of esophagus; composed of ringed cartilage covered by ciliated mucous cells which collect dust and usher it toward pharynx |
| bronchi | splits into right and left from trachea |
| bronchioles | branched off of bronchi, much smaller and will terminate into alveolar sacs that contain alveoli |
| alveoli | where the O2 diffuses into capillary where it is picked up by RBCs which transport CO2 into alveoli to be expelled |
| hemoglobin | protein inside erythrocytes that bind to 98% of O2 rapidly and reversibly, can bind to 4 O2 molecules with its iron atoms in the heme group |
| what is the cooperativity phenomenon commonly found w/ Hb? | when 1 O2 molecule binds to Hb, oxygenation of the other heme groups on that Hb is accelerated - also the same if 1 grp releases an O2, the release of all other O2 is accelerated |
| HbO2 dissociation curve has what kind of curve? | sigmoidal |
| O2 dissocation curve shifts to the right when there is an increase in any of the following | CO2 pressure, H+ concentration (pH decrease), or temperature |
| Bohr shift | shift of oxygen affinity due to pH |
| if O2 dissociation curve shifts to the right, what does this mean to the affinity of Hb for O2? | lowering of the Hb affinity for oxygen |
| effect of CO on Hb | CO has a much greater affinity for O2 and will shift the HbO2 dissociation curve to the left |
| CO2 is carried in the blood in 1 of 3 forms | in physical soln, bicarbonate ion, in carbamino cmpds (combined with Hb and other proteins) |
| which is the most common way to carry CO2? | as a bicarbonate ion - formation governed by carbonic anhydrase (in RBC) |
| carbonic anhydrase catalyzes which rxn? | CO2 + H20 --> HCO3- + H+ |
| what is the chloride shift? | phenomenon where chlorine moves out of the cell to balance electrostaic forces when the bicarb ion diffuses into the cell (when CO2 is absorbed in the lungs) |
| what is the Haldane effect? | when Hb is saturated with O2, its capacity to hold CO2 is reduced - promotes dissociation of CO2 from Hb in presence of O2. reduced Hb (Hb w/o O2) then has greater capacity to form carbamino Hb |
| how does the body compensate in cases of acidosis | increasing breathing rate to expel more CO2 and raise the pH of blood |
| oxygenation of Hb shifts the bicarb buffer equation towards... | CO2 formation so that it will be released from RBCs |
| rate of breathing is affected by... | central chemoreceptors located in medulla and peripheral chemmoreceptors in carotid arteries and aorta |
| central chemoreceptors monitor... | CO2 concentration in blood and increases breathing when levels get too high |
| peripheral chemoreceptors monitor.. | oxygen conc and pH |
| the bends | bubbles that can form when divers come to the surface to quickly - pressure decreases and gas volume increases and the N2 doesn’t have enough time to diffuse out of the blood into lungs will form bubbles |
| function of lymphatic system | recycles interstitial fluid and monitors blood for infection; reroutes low soluble fat digestates around small capillaries of the intestine and into large veins of neck |
| how to enter lymph system | interstitial fluid flows btw overlapping endothelial cells, large particles push their way in btw cells but cannot push their way out |
| pressure of interstitial fluid | typically slightly negative; as it rises towards zero, lymph flow increases |
| factors that affect interstitial pressure | blood pressure, plasma osmotic pressure, interstitial osmotic pressure (from proteins, infection response) and permeability of capillaries |
| where does the lymph system empty into? | large veins at the thoracic duct and the right lymphatic duct |
| how is interstitial fluid propelled thru its valves? | smooth muscle in walls of large lymph vessels contract when stretched and lymph vessels may be squeezed by adjacent skeletal muscles, body movements, arterial pulsations, and compression from objects outside the body |
| function of blood | regulates extracellular environment of body by transporting nutrients, waste products, homones, and heat; protects body from injury and foreign invaders |
| blood composition | (from lowest to highest density) plasma, white blood cells, red blood cells |
| plasma contains... | water, ions, urea, ammonia, proteins, organic and inorganic compunds |
| important proteins in plasma | albumin, immunoglobulins, clotting factors |
| albumin | transports fatty acids and steroids, and regulates osmotic pressure of blood |
| red blood cells | aka erythrocytes, no organelles, do not reproduce or undergo mitosis, disc shaped vesicles whose function is to transport O2 and CO2 |
| white blood cells | aka leukocytes, contain organelles but no hemoglobin and protect the body from foreign invaders |
| when/where do RBC lose their nucleus? | while still in blood marrow - and will lose rest of organelles shortly after in the blood stream |
| platelets | small portions of membrane bound cytoplasm torn from megakaryocytes, tiny cells w/o nucleus, but contain other organelles - designed to avoid adherence to healthy endothelium and adhering to injured endothelium |
| 3 steps of coagulation | formation of prothrombin activator (12+ coag factors form complex) -> prothrombin to thrombin --> thrombin catalyzes fibrinogen to fibrin that attach to platelets and form tight plug |
| innate immunity includes | skin as barrier, stomach acid and digestive enzymes, phagocytic cells, and chemicals in blood |
| what happens in inflammation? | dilation of blood vessels, increased permeability of capillaries, swelling of tissue cells, migration of granulocytes and macrophages to inflamed area |
| order of innate immunity defense | (1)skin/digestive defences (2) local macrophages (3) neutrophils (drawn in by chemotaxis) (4) neutrophils engul necrotic tissue and bacteria |
| macrophages made from.. | monocytes |
| what are the two types of acquired immunity? | humoral/B-cell immunity or cell-mediated/T-cell immunity |
| humoral/B-cell immunity | promoted by B-lymphocytes which make free antibodies that bind to antigens (presented by macrophages) |
| humoral immunity is effective against … | bacteria, fungi, parasitic protozoans, viruses, and blood toxins |
| what happens when b-lymph Ab contacts matching antigen? | B-lymph with helper T cell differentiates into plasma cells and memory B-cells so plasma cells can synthesize free antibodies |
| when free antibodies contact the specific antigen, then bind to it and then... | cascade of rxns begin that involve blood proteins (complement) that cause antigen bearing cell to be perforated |
| primary response | first time the immune system is exposed to antigen, requires 20 days to reach its full potential |
| secondary response | faster and more potent immune response upon re-infection that takes about 5 days to reach full potential, comes from the memory B cells |
| t-lymphocytes mature in the... | thymus |
| cell-mediated immunity is effective against … | infected cells |
| t-lymphs are tested against … | self-antigens - antigens expressed by normal cells of the body |
| when t-lymphs bind to self-antigen, it can be.. | destroyed, and if not destroyed, it is released into lymphoid and differentiated into helper T- cells, memory T cells, suppressor T-cells, and killer T-cells |
| helper T cells | assist in activating b-lymphocytes and killer and suppressor t-cells |
| memory T cells | similar function to memory B cells |
| suppressor T cells | play negative feedback role in immune system |
| killer T cells | bind to antigen carrying cell and release perforin; can attack many cells b/c they do not phagocytize their victims, responsible for fighting some forms of cancer and attacking transplanted tissue |
| blood types are identified by... | A and B surface antigen |
| genes that produce the A and B antigens are... | codominant |
| Rh factors | surface proteins on RBCs, nonfunctional means Rh - and functional means Rh+; these become an issue with pregnancies |
| surfactant | lipid molecule produced by lung cells that decreases surface tension in alveolar walls to prevent alveoli collapse |
Created by:
miniangel918
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