EXSS 276 Midterm Full Exam 2025

Oxygen carrying in blood - -blood leaves the lung, fully saturated and once the hemoglobin is in the target tissue, it begins to desaturate, releasing oxygen Hemoglobin when at the lung, picks up oxygen, but other areas releases lots of oxygen Process of picking up and releasing only occurs Blood must be in capillaries where the blood composition of the blood can be changed to structure the vessels to pick up or release blood Signals for hemoglobin to saturate or desaturate - -ration of oxygen to CO2 Ph Temperature Hemoglobin also carries a large amount of CO2 - -(almost 25% of waste product is carried by it) It will only carry CO2 when it is desaturated; when saturated, it won't (just start desaturation) Metabolism produces the CO2 and the hemoglobins desaturate in areas that are doing lots of metabolism, but when the hemoglobin gets to the lungs, the capillaries are different, so it releases CO2 at the lungs and picks oxygen back up (saturation) Anemic people (due to poor levels of hemoglobin or rbcs): you can't pick up as much oxygen or CO2 thus your metabolism doesn't work well to produce ATP, and when it is producing the ATP, the CO2 can't be thrown out which inhibits energy production even further - thus lethargy Erythropoiesis or Hemopoiesis - -process by which rbcs are made Reduced levels of oxygen in the blood stimulate kidney Kidney stimulates by releasing erythropoietin which stimulates red bone marrow to undergo enhanced erythropoiesis producing more rbcs which Stem cell (hemocytoblast) — committed cell (proerythroblast) — phase 1: ribosome synthesis — phase 2: hemoglobin accumulation — phase 3: ejection of nucleus — erythrocytes EXSS 276 EXSS 276 Reduced levels of oxygen in the blood stimulate kidney - -hypoxia: low levels of oxygens which will usually occur because you have lower levels of rbcs and hemoglobin (due to diet, anemia, or even environmental conditions) Epo - -doping agent associated with endurance activities Takes pharmaceutical basis of erythropoietin and injecting or swallowing it Increases hematocrit and hemoglobin but the problem is when it moves to milkshake level it makes the heart work harder # of cases where triathletes and cyclists or distance runner die of heart attack during activity Blood isn't super viscous when you're resting, but when you're sweating a lot during activity, you can never replenish the fluid as quickly as you lose it, plasma water is getting smaller and formed elements are dissolved in this so the blood because more viscous (already more viscous because of EPO) Heart can't pump blood adequately Note: most water in your sweat comes from plasma water Most water in your sweat comes from - -plasma water Globin - -alpha and beta protein chains Recycling of amino acids for new rbcs Blood doping - -injecting previously stored rbcs before an athletic event (more cells available to deliver oxygen to tissues - hard to detect because you're using your own blood other than looking for track marks) Dangerous (increases blood viscosity and forces heart to work harder) Banned by Olympic committee Hypoxia (altitude) - -another form to raise hemoglobin level Cause levels of blood to stimulate the kidney to produce erythropoietin, thus more rbcs Training and being exposed to altitude, causes your hemoglobin to increase thus your performance increases Not banned - why a lot of teams go higher in altitude to train EXSS 276 Problem: you have a window of time, as soon as you go to sea level, the body reduces erythropoietin and RBC and hemoglobin production goes down so high values of hemoglobin drop rapidly so you have 7-10 days until you're back to normal Reason why athletes can do well at competition but at the Olympics they suck because they have to go through 2 weeks of qualifying Anemia - -either not enough rbcs (low hematocrit) or have rbcs but not enough hemoglobin in them (both types have the same effect) Anemia can be due to - -decreased erythropoiesis Increased destruction of rbcs Increased destruction of hemoglobin Anemia can result in - -decreased capacity to carry gases (delivering O2 and getting rid of CO2) Decreased acid buffering capacity (hemoglobin is able to accept hydrogen ions so it is a buffer - if you have a form of anemia where you don't have as much hemoglobin, you lose the buffering capacity and can't accept enough hydrogen ions so pyruvic acid stays as lactic acid and disassociates and becomes acidic and you can't produce as much ATP through metabolism) Blood groups and types - -Type A Type B Type AB Type O Type A - -A antigen (glyco-proteins - protein structures with carb structures to them) Anti-B antibody: made by the liver and ride on the plasma cells Type B - -B antigen Anti-A antibody Type AB - -both A and B antigens EXSS 276 EXSS 276 Neither antibody "universal recipients": can take A or B type Type O - -O: Neither A nor B antigen Both Anti-A and Anti-B antibodies "universal donors": give blood to anyone due to lack of antigens Heart myocardium is comporised of - -myocardial muscle cells and connective tissue Cardiac muscle - -super slow muscle (super Type I - slow oxidative) Lots of mitochondria, capacity for aerobic metabolism, ability to metabolize lipids as an energy source Inter-connected in an electrical synergy and if you send a signal to one myocardial muscle cell, it will pass it on to the ones around it The more myocardial muscle cells, the stronger the tissue Bi-directional contraction - goes in multiple directions unlike skeletal muscle (atriums push down and ventricles push down) The vast majority of myocardial muscle tissue is in - -the ventricles of the heart Vast majority of the ventricle is in the left vs. The right Atriums have minimal myocardial muscle tissue - -not effective pumps, the ventricles are Have a heart attack in the atrium not the ventricles Priming pumps Low pressure pumping - -right atrium and ventricle (pump to lung) Does not need powerful pump to go to the lungs which are nearby High pressure pumping system - -left atrium and ventricle (pump to whole body) High pressure pumping system: needs more because it's going to the whole body Bi-directional contraction - -through intrinsic conductive system of the heart EXSS 276 EXSS 276 Anatomically orient the trial muscle in one direction Twist the entire muscle and orient the ventricular muscle in a different direction Then you send an electrical signals to the atrium and the contraction goes from the top down Then the electrical signal stops mid-point is propagated down the inter-ventricular septum and then stops at the apex, where it then moves upward Ectopic beats - -irregular heart contractions not utilizing the intrinsic conductive system Causes: dead tissue because you drank to much caffeine (irritant to the tissue of electrical conductive system of the heart) Ever time you have a heartbeat, you pump out about - -70-75 ml of blood Cardiac output - -around 5L of blood per minute (entire blood volume - if you're around 65 bpm) Heart rate faster = higher amount of blood circulated Exercising = circulating faster Greater the cardiac output, the greater absolute amount of oxygen you can get to the mitochondria in the muscle cells for metabolism Pump mechanism is intermittent - -blood shoots out and then doesn't Systole and diastole Contraction - -systole Blood leaves the LV Relaxation - -diastole No contraction and blood does not leave the LV Passive filling - -opening of the mitral valve due to the filling of the atrium with blood, blood leaks into the left ventricle and fills it up without a contraction of the atrium Eosinophils - -mediate allergic responses, fight viruses; combat parasitic worms Natural killer (NK) cells - -destroy viruses and tumor cells EXSS 276 EXSS 276 Release perforins which insert into the plasma membrane of pathogen cells; makes the cell membrane leaky resulting in lysis Release molecules into pathogen cells which cause apoptosis Plasma B cells - -produce antibodies that bind specific pathogens (aka immunoglobulins, or lg's) Memory B cells - -serve as a template for further antibody production to specific pathogens T helper cells - -recognize pathogens and secrete cytokines which cause proliferation of other T and B cells Cytotoxic T cells - -destroy targeted pathogen Memory T cells - -initiate faster response to 2nd insult of pathogen Secondary lymphatic organs - -sites where most immune responses occur Lymph nodes Spleen Lymphatic nodules Lymph - -interstitial fluid that travels through lymph capillaries to the lymph nodes Bicuspid valve - -Left atrium from left ventricle Aortic semi-lunar valve - -left ventricle from the aorta Tricuspid valve - -right atrium from right ventricle Pulmonary valve - -RV from large pulmonary vein Valves - -one-way valves designed to let blood flow from one chamber of the heart to the next or large vessel They have large open aperture (unless you have stenosis) Prevented from having bi-directional flow from tendon structures that prevent regurgitation (unless you have prolapse) EXSS 276 EXSS 276 EXSS 276 Valve flaps overlap and when blood pushes through and opens them out, it moves through and then the blood moves through and the flaps come back down and the tendons keeps them open Stenosis - -anatomical issues where the valve opens too narrow Blood flows and the valve shuts, but to get the same volume of blood to flow from one chamber to the next, you have to have higher pressure w