Lucy, a new Army recruit, stood in formation for long periods of time without moving an inch. She eventually became lightheaded and fainted because her blood pressure dropped. What might have caused her blood pressure to drop?
What will be an ideal response?
Venous return depends largely on muscle contraction to move blood through the veins. If a person stands upright for long periods of time without moving much, the muscles don't contract much; thus, as a result of poor venous return, the person may experience a drop in blood pressure.
You might also like to view...
The first child conceived using IVF was born in ____
a. 1958 b. 1968 c. 1978 d. 1988 e. 1998
Three species of tigers have become extinct due to overharvesting or habitat destruction. This is an example of
A. mass extinction. B. background extinction rate. C. sympatric speciation. D. increased extinction rate by human activity. E. allopatric speciation.
Turgor is most directly related to the plant cells'
A. gravity potential. B. pressure potential. C. solute potential. D. osmosis. E. total water potential.
Why does urine frequently have an acidic pH?
A. The kidneys filter and excrete H+ from the blood. B. The kidneys absorb H+ ions and excrete bicarbonate ions. C. The kidneys produce H+ in the process of filtering the blood. D. The blood has an acidic pH and the kidneys produce urine similar to the pH of the blood. E. There is a high concentration of hydrochloric acid (HCl) in the urine, making it highly acidic.