A-LevelBiologyTransport in mammals9700/12 · May/June 2020 · Q311 Mark
What correctly describes the significance of the increase of the red blood cell count of humans who move from living at low altitude to high altitude?
AAfter a few weeks at high altitude, the number of red blood cells increases to compensate for the lower availability of oxygen in the air.
BAt high altitude, the bone marrow produces more red blood cells to provide binding sites for the increased number of oxygen molecules available.
CAt high concentrations of oxygen in the blood, a cytokine stimulates the production of red blood cells to increase the oxygen-carrying capacity of the blood.
DAfter only a few days at high altitude the number of red blood cells increases considerably to compensate for the lower availability of oxygen in the air.
✓ Correct answer
A: After a few weeks at high altitude, the number of red blood cells increases to compensate for the lower availability of oxygen in the air.
Practise more questions on this topic
Oracle Prep sorts past-paper questions by topic, so you can drill Transport in mammals and see which topics are most likely to come up next.
Sign up free →