If you have studied enzymes its a similar concept. Cells have proteins on the surface of their cell which hormones bind to (called receptors) The receptor must be a complimentary shape to the hormone for it to bind. Only target cells have the receptor with the complimentary shape so only these cells will be affected.
I think the answer would be medium
<span>Carbon dioxide diffuses 20 times faster than oxygen gas
It is estimated, however, that the diffusing capacity of carbon dioxide is from 400 ml to 450 ml per minute under resting conditions and the diffusion capacity for oxygen under resting conditions is 21 ml per minute.</span>
C I’m pretty sure. The first step is the rate determining step
