Ch 18 Blood 3
Card Set Information
Ch 18 Blood 3
What are the two principle functions of Erythrocytes?
–Carry oxygen from lungs to cell tissues
–Pick up CO2 from tissues and bring to lungs
Determined by surface glycoprotein and glycolipids
_____ proteins (spectrin and actin) give membrane
durability and resilience
•Stretch and bend as squeezed
through small capillaries
33% of cytoplasm is?
____ million hemoglobin molecules on one RBC
O2 delivery to _______ and CO2 transport to _______.
–Produces carbonic acid from CO2
–Important role in gas transport and pH balance
Carbonic anhydrase (CAH) in cytoplasm
Each hemoglobin (Hb) molecule consists of?
–Four protein chains—globins
–Four heme groups
–Nonprotein moiety that binds O2 to ferrous ion (Fe2+) at its center
–percentage of whole blood volume composed of RBCs
•Men 42% to 52% cells; women 37% to 48% cells
Hematocrit (packed cell volume)
•Men 13 to 18 g/dL; women 12 to 16 g/dL
Hemoglobin concentration of whole blood
•Men 4.6 to 6.2 million/mL; women 4.2 to 5.4 million/mL
RBC values are lower in women because?
–Androgens stimulate RBC production
–Women have periodic menstrual losses
–Hematocrit is inversely proportional to percentage of body fat
_____ million RBCs are produced per
Average lifespan of a erythrocyte is?
about 120 days
Development of a erythrocyte takes
•3 to 5 days
–Reduction in cell size, increase in cell number, synthesis of hemoglobin, and loss of nucleus
In the negative feedback controle of erythrocyte homeostasis a drop in RBC count causes?
In the negative feedback controle of erythrocyte homeostasis kidney production of erythropoietin stimulates?
In the negative feedback controle of erythrocyte homeostasis RBC count increases in __ to ___ days
3 to 4
What are the stimuli for increasing erythropoiesis?
–Low levels O2 (hypoxemia)
–Increase in exercise
–Loss of lung tissue in emphysema
Erythrocyte Death and Disposal:
RBCs lyse in narrow channels in the?