•Decrease in Oxygen in
blood causes heart rate to increase initially in order to maintain Oxygen transport
•Amount of water in
blood plasma decreases after about a week
–Decreases plasma
volume without changing volume of red blood cells
–Blood can carry
greater quantity of Oxygen
–Prolonged hypoxia
stimulates bone marrow to produce more red blood cells
•After a week, heart
rate normalizes but stroke volume (volume pumped by left ventricle) decreases, leading to net drop in
cardiac oxygen output