Which of the following following terms best describes air?
a)element
b)compound
c)mixture
d)none of the above

Which blood cell spend most of their time in the lymphatic system?

What is responsible for the uneven heating between the poles and the equator on any given day

Cells a and b are the same size and shape, but cell a is metabolically quiet and cell b is actively consuming oxygen. oxygen will diffuse more quickly into cell because . b the oxygen molecules inside cell b have a higher kinetic energy b. a its membrane transport proteins will not be saturated c. a the diffusion gradient there is shallowerd. b the diffusion gradient there is steeper