EXSC 224 1st EditionExam # 3 Study GuideEnd of Chapter 16- Hypo-thyroid disorder: cretinism, myxedema, and goitero Myxedema: These individuals tend to have a round face due to larger amounts of connective tissue.o Goiter: Thyroid swells because iodine doesn’t bind to thyroglobin. This tends to occur in people living far from the sea (they don’t get iodine from sea salt).- Hyper-thyroid disorder: Grave’s disease- Calcitonin: made by parafollicular cells in thyroid glando Operates by humoral negative feedback mechanismChapter 17- Components of whole blood: cells, proteins, electrolytes o 55% plasma – plasma is 90% water, rest is soluteso 45% formed elements – leukocytes, erythrocytes, and platelets- Hematocrit – the proportion of whole blood that is erythrocytes- Erythrocytes – anucleate biconcave disc, 97% hemoglobino Spectrin – protein that gives flexibility- Erythropoietin – increases red blood cell production by stimulating red bone marrow- Know this diagram very well:- Erythrocyte disorders: anemia, thalassemias, sickle-cello Anemias – hemorrhage, hemolysis, aplastic, dietary iron deficiency, athlete’s anemia, pernicious anemia- Leukocytes – granulocytes (neutrophils (50-70%), eosinophils, basophils) and agranulocytes (lymphocytes (25-45%), monocytes (3-8%))- Diapedesis – the passage of white blood cells through capillary walls and into tissues to fight infection- Chemotaxis – injured tissue sends chemical signals to order to bring white blood cells to the site of infection- Know functions of the different types of leukocyteso Neutrophil – phagocytize harmful microorganismso Eosinophil – trap and kill substances, modulate inflammatory responseo Basophil – contains histamine, an anti-inflammatoryo Monocyte – a macrophage- Leukocyte disorders: leukemia and mononucleosis- Know developmental pathway of plateletso Hemocytoblast → megakaryoblast → promegakaryocyte → megakaryocyte → platelets- Coagulation – a fibrin clot forms and traps red blood cellso Vascular spasm → platelet plug formation → fibrin clot formation- Know the summary of formed elements table 17.2- Know ABO blood group table 17.4o You have antigens of your blood type (ex: A blood has A antigens)o Your body has antibodies against other blood types- Rh factor – a subclass of antigen reactivityo 85% of Americans are Rh +o Erythroblastosis fetalisChapter 18- The heart – a living, mechanical device with 4 pumps (2 atrial, 2 ventricle)o Pressure of blood is greater leaving the heart than entering- Pulmonary Circuito Delivers oxygen-poor blood to lungso Pressure of blood leaving pulmonary arteries: 25 mm Hgo Pressure arriving in pulmonary veins: 2 mm Hgo Blood flows down this pressure gradient- Systemic Circuito Delivers oxygen-rich blood to organs and tissueso A high pressure system, since blood must be pumped against gravityo Pressure of blood leaving aorta: 120 mm Hgo Pressure entering right atrium via vena cava: 2 mm Hg- Valves – are one way, pressure actuated flaps of connective tissueo Atrioventricular valves: tricuspid and bicuspid (mitral) Supported by chordae tendineae, which are connected to papillary muscles that prevent valve failure.o Semilunar valves: aortic and pulmonary valves Consist of 3 cupso Pathology: incompetent (leaky) valve and stenosis (narrowing of valve, can be a birth defect or be the result of a build-up of scar tissue)- Pericardial layers of the hearto Fibrous pericardium – surrounds hearto Parietal and visceral layers of serous membrane – continuous and secrete a ground substance that lubricates the hearto Myocardium – the smooth muscle cells of the hearto Endocardium – innermost layer that lines the atria and ventricles- Cardiac monocytes are small and have many branches, while skeletal muscles are very long and do not have a lot of origins and insertionso Cardiac monocytes are connected end to end by intercalated discs.- Shapes of left and right ventricleso Left ventricle – cylindrical, more muscular, 3 x thicker than wall of right ventricleo Right ventricle – crescent, thinner, weaker wallo Separated by the interventricular septum- Coronary circulation – supplies muscles of heart with bloodo Coronary artery bypass graft (CABG)o Coronary stento Balloon angioplasty- Cardiac muscle – specialized striated muscleo Automaticity – the ability to generate an action potential w/o external stimulio Gap junctions allow heart to contract as a unito Oxygen-dependent to produce ATP- Sliding filament theory – thin filaments slide past thick filaments so that myosin and actin overlap more; accomplished by cross-bridge cycling- Primary function of the heart – to pump blood though pulmonary and systemic circuitso Cardiac output (Q) = heart rate X stroke volume- Intrinsic regulation of heart rate: automaticity, sinoatrial node, atrioventricular node, Purkinje fibers, cardiomyocyteso Automaticity – SA node firing rate is 100 beats/min The heart will still beat if the SA node is damaged, it will just be irregular and not as strong (AV node fires at 70 beats/min)o SA node – pacemaker of heart (determines heart rate); located in right atrium Primary function: depolarize and make rest of heart contracto AV node – there is a pause when the signal is transmitted from the SA nodeo Bundle of His and bundle branches – transmit action potential through hearto Purkinje fibers – carries signal up the lateral sides of the heart- 3 Phases of SA node action potential:o Phase 4 – leaky Na+ channelso Phase 0 – depolarization; Ca2+ channels are openo Phase 3 – repolarization; K+ channels open- 5 Phases of ventricular myocyte action potential:o Phase 0 – depolarization; Na+ channels openo Phase 1 – Na+ channels close and K+ channels openo *Phase 2 – K+ channels close and Ca2+ channels open (calcium entry delays repolarization so myocytes remain depolarized)o Phase 3 – repolarization; Ca2+ channels close, K+ channels reopeno Phase 4 – re-establish Na+/K+ gradient- If a cell remains depolarized, it cannot depolarize again.- Extrinsic regulation of heart rate:o Sympathetic – increases heart rate; norepinephrine and epinephrine detected by adrenergic receptor B1, found in SA and AV node and ventricular myocyteso Parasympathetic – decreases heart rate; Acetylcholine detected by muscarinic receptor M2, which is found in SA and AV nodeo These regulate the rate at which Na+ enters the cell-