Erythrocyte Physiology Flashcards
Hematocrit
Height of RBCs / total height (in centrifuged blood sample)
Functions of blood (4)
Deliver nutrients and oxygen
remove waste products
maintain homeostasis
circulate hormones, immunoglobulins
Composition of blood (2)
Plasma - solution component of blood: electrolytes, proteins, carbohydrates, lipids, clotting factors
Formed elements - erythrocytes, leukocytes, platelets
Functions of erythrocytes (3)
Carry O2 from lungs to body
Carry CO2 from body to lungs
Acid/Base buffering
HIF
Hypoxia inducible factor - transcription factor that upregulates production of erythropoietin in hypoxic conditions
EPO stimulated by
HIF (TF)
Anemia
Low renal blood flow
Central hypoxia (high altitude, pulmonary disease)
Regulation of Erythrocytes
Tissue oxygenation decreases EPO secretion, decreasing amount of RBCs produced
Important because too many RBCs will impede blood flow
Hypochromic anemia
deficient transport of transferrin
Oxygen capacity
maximum amount of oxygen that can be carried by hemoglobin in blood (all four hemes bound O2)
Oxygen Saturation
how much oxygen is actually being carried by the blood ( 19.5 mL O2/dL)
Oxygen content
Maximum capacity x saturation: Spots occupied by oxygen as a percentage of total available spots