How do cells in an embryo become different types of cells?

Wich level of organization includes all the other levels or organizations

Why do mountaineers become breathless as they reach high altitudes

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