M7 - Blood Flashcards
Blood fxns
Transport, defense, maintenance of homeostasis
Components of blood
Plasma - 55%, water, protein, nutrients
Buffy coat - 1%, leukocytes and platelets
Hematocrit - ~44%, erythrocytes
Hematopoeisis
Production of blood cells, produced in liver and spleen before birth, produced in red bone marrow after
Leukemia
Overproduction leads to non-functional cells, capacity for immune response is diminished
Erythrocytes
4 hemes which binds to O2, 4 globins which contain iron atom and bind to CO2
Thromobocytes
Platelets, clotting
Leukocytes
White blood cels, defense
Granulocytes
Contain granules, basophils, eosinophils, neutrophils
Basophil
<1% WBC, inflammation, allergic rxns - release histamine and heparin, parasites
Eosinophil
2-4%, immune modulators, parasites, allergic rxns, phagocytic
Neutrophil
50-70% WBC, kill bacteria, phagocytic, bacterial infection
Agranulocytes
Cells that lack granules, monocyte, lymphocyte
Monocyte
2-8% of WBC, nonspecific immune response, bacterial and other infections, macrophages
Lymphocyte
20-30% of WBC, primary cells of lymphatic sys, specific immunity, T, B, NK cells
Blood type
Determined by surface antigen present on erythrocyte
Type O
Absence of A and B antigens on RBC
Donor compatibility
Determined by antibodies
Type O
Universal donor (no antigens)
Type AB+
Universal acceptor (all antibodies)
Rh factor and pregnancy
Rh- mother, Rh+ baby, problem for second pregnancy because Rh+ antibodies destroy Rh+ RBCs
Blood vessels
Arteries - thick walls w small lumens, appear rounded
Veins - thinner walls with big lumens, appear flat
Tunica intima
Artery - wave endothelium, internal elastic membrane
Vein - smooth endothelium, absent internal elastic membrane
Tunica media
Artery - thicket layer, full of smooth muscle and elastic fibers
Vein - thinner than tunica externa, smooth muscle and collagen fibers
Tunica externa
Artery - thinner than tunica media, collagen and elastic fibers, contains nervi and vasa vasorium
Vein - thickest layer, collagen and some smooth muscle, contains nervi and vasa vasorium
Blood pathway
Heart –> elastic artery –> muscular artery –> arteriole –> venule –> medium-sized vein –> large vein
Capillary types
Continuous, fenestrated, sinusoid
Continuous capillary
Most common, allow least amt of exchange
Fenestrated
Bigger holes, allow more exchange
Sinusoid
Like swiss cheese, allow most of exchange, incomplete basement membrane
Capillary
Each capillary bed is fed by arteriole, precapillary sphincters regulate blood flow to tissues, comprised of smooth muscle
How blood gets back to heart
Muscle pump, respiratory pump, valves
Varicose veins
Blood pools in legs, nonfunctional valves
Collateral circulation
Alternative pathways for delivering blood to region of body
Blood artery pathway
Heart –> aorta –> artery –> arteriole –> capillary
Blood vein pathway
Venule –> vein –> vena cava –> heart
