A student plants pea seeds in three identical pots. Each pot contains three seeds. The first pot contains potting soil, the second pot contains clay and the third pot contains sand. The seeds are given the same amount of water and sunlight for three weeks. What is the independent variable in this experiment?

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