S t u d y G u i d e E x a m I I I P E T 3 3 2 2 A n a t o m y a n d P h y s i o l o g y I N o v e m b e r 7 2 0 1 1 Chapter 19 The Blood Overview Blood Composition and Functions 1 Describe the composition and physical characteristics of whole blood Explain why it is classified as a connective tissue Denser more viscous than water and slightly sticky 38 C 100 4 F pH of 7 35 7 45 saturated with oxygen is bright red unsaturated with oxygen is dark red Blood constitutes 20 extracellular fluid amounting to 8 of the total body mass 5 6 L in male and 4 5L in female Several hormones regulated by neg feedback ensure that blood volume and osmotic pressure remain relatively constant Aldosterone ADH and atrial natriuretic peptide regulate how much water is excreted in urine 2 components 1 blood plasma 55 2 formed elements 45 which are cells and cell fragments Cells are more dense than plasma so go to bottom RBCs and WBCs are formed elements Platelets 1 of formed elements Form thin buffy coat between packed RBCs and plasma in centrifugion CT because it has the same origin as other CT mesodermal and it connects the body systems together bringing the needed O2 nutriends hormones and other signaling molecules and removes wastes 2 List eight functions of blood 1 Transportation transports O2 from lungs to body cells and CO2 from body cells to lungs for exhalation Carries nutrients from GI tract to b c and hormones from endocrine glands to other b c transports heat and waste products from the body 2 Regulation maintain homeostasis of all body fluids Helps regulate pH through use of buffers Adjust body temp 3 Protection clotting protects from excessive loss these are 3 general functions each of these 3 have many functions within Blood also influences water content of cells Fights disease Blood Plasma 3 Discuss the composition and functions of plasma 91 5 water and 8 5 solutes most are proteins 7 so they 1 5 is other solutes Hepatocytes liver cells synthesize most plasma proteins which include albumins 54 globulins 38 fibrinogen 7 Plasma proteins are produced during certain immune responses Disables invading antigens clots regulate nutrients in blood homeostasis Formed Elements 4 Describe the structure function and production of erythrocytes RBCs Contain oxygen carrying protein hemoglobin gives blood its red color Bioconcave discs with diameter of 7 8um PM is strong and flexible Highly specialized for their O2 transport function No nucleus so all space is available for O2 transport Generate ATP anaerobically cus they don t have mitochondria One RBC has 280mill hemoglobin molecules Hemopoiesis Is the process by which the formed elements of blood develop Red bone marrow is highly vascularized CT most CT develops from mesenchyme RBCs live about 120 days Ruptured ones are removed and destroyed by phagocytic macrophages in spleen and liver Life cycle 1 macrophages in spleen liver red bone marrow phagocytize ruptured blood cells 2 globin and heme portions split apart 3 globin is broken into a a 4 iron is removed from heme as Fe3 and associates with transferrin a transporter 5 in muscle fibers liver magrophages of spleen and liver Fe3 detaches from transferrin and attaches to ferritin iron storage protein 6 Fe3 reattaches to transferrin after release from storage site or absorption from GI tract 7 this transferrin is brought to red bone marrow where RBC precursor cells take it for use in hemoglobin synthesis iron a a B12 all needed for synthesis of hemoglobin 8 erythropoiesis results in production of RBC enter circulation 9 non iron portion of heme is turned to biliverdin green pigment and then to bilirubin yellow orange pigment 10 Bilirubin enters blood and goes to liver 11 it is released by liver cells into bile goes to small intestine then to large 12 here bacter converts bilirubin to urobilinogen 13 urobilnogen is absorbed back into the blood turned to urobilin yellow pigment and excreted in uring 14 most urobilinogen is out in feces in stercobilin brown pigment RBC formation starts in rbm with proerythroblast which divides several times and produces cells to synthesize hemoglobin Ejects nucleus n becomes a reticulocyte This loss causes the cell to indent in pass from rbm to bloodstream by squeezing between endothelial cells of blood capillaries Develop into RBCs 1 2 days after release from rbm Hypoxia cellular oxygen deficiency 5 Describe the chemical makeup of hemoglobin hemoglobin has globin protein with 4 polypeptide chains 2A and 2B and heme ringlike nonprotein pigment that binds to each of the 4 chains An iron ion is at the center of the heme that can combine with O2 O2 from lungs binds to iron ion Hemoglobin releases O2 which diffuses into interstitial fluid then into cells It transports 23 of total CO2 a waste product of metabolism remaining CO2 is dissolved in plasma or carried as a bicarbonate ions Some CO2 binds with a a in the globin In lungs it is released and exhaled 6 Give examples of disorders caused by abnormalities of erythrocytes Explain what goes wrong in each disorder Anemia reduced number of RBCs or decreased amount of hemoglobin in blood Fatigue intolerant to cold pale skin shortness of breath delayed growth and development in children Low hemoglobin circulation Lack of O2 for ATP and heat production Iron deficiency anemia most common type Inadequate intake absorption of iron excessive loss Women due to menstrual blood loss GI losses like ulcer Megaloblastic anemia inadequate intake of folic acid B12 RBmarrow produces abnormal large RBCs Drugs that alter gastric secretion or treat cancer can cause it Pernicious anemia insufficient hemopoiesis Inability of stomach to produce intrinsic factor Hemorrhagic Anemia excessive loss of RBCs from bleeding of large wounds or stomach ulcers or heavy menstruation Hemolytic anemia RBC PM rupture prematurely Hemoglobin pours into plasma and can damage filtering units in kidneys From inherited defects or parasites toxins antibodies Thalassemia deficient synthesis of hemoglobin RBCs are small pale short lived Usually in countries on Mediterranean sea Aplastic anemia destruction of RBmarrow Caused by toxins gamma radiation certain meds that inhibit enzymes needed for hemopoiesis Sickle Cell Disease SCD have Hb S abnormal hemoglobin This makes erythrocytes sickle shaped which makes them rupture easily They break down prematurely leading to anemia Sickle cells tend to stick together corming clumps and blockages It is inherited need 2 sickle cell
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