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9 Cards in this Set
- Front
- Back
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Blood transports:
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O2 from lungs
CO2 to lungs nutrients from GI tract waste products from cells hormones from endocrine glands |
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Blood regulates:
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pH through buffers
body temp through heat-absorbing &coolant properties of H2O osmoic relations through Na content |
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Blood protects against:
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blood loss through clotting
foreign microbes and toxins through WBC actions |
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Erythrocytes (Red Blood Cells)
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Biconcave discs which at maturity lack a nucleus
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Erythrocyte characteristics
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rellatively large surface area: volume ratio at maturity not only lack nucleus but also lack mitochondria, microtubules, ER and protein synthesizing ability
primary function-transport respiratory gases |
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Erythrocyte production
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early weeks embryonic life: yolk sac
middle trimester: liver and spleen later gestation/after birth: bone marrow age 5: all marrow adult: proximal epiphyses of humerus and femur, and marrow of the flat bone of he cranium, ribs, sternum and body of vertebrae |
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RBC membrane: osmotic relationships
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RBCs-hypotonic env.-membrane ruptures-hemolysis or laking
RBCs-hypertonic env.-cell shrinks-crenation or plasmolysi |
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Destruction of RBCs
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life span:120days
destroyed by reticuloendothelial cells in the liver and spleen |
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Regulation of BRC production
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any decrease in the oxygen carrying capacity of the tissues results in an increase in RBC production eg anemia, hemorrhage, high altiude, destruction of major portions of bone marrow leading to hyperplasia of the remaining bone marrow
NOTE: its not the concentration of RBCs but the oxygen carrying capacity that controls the rate of RBC production |
