Marine: explain how deep water currents affect the number of organisms found in the area by circulating nutrients.

Surface currents affect the climate by the force of the wind and water temperatures and that's what affects the climate.  

The answer will be d

Mitochondria produce atp, a high energy compound. atp is used for all sorts of enzyme-mediated reactions, such as making proteins/nucleotides/etc, certain compounds cross the cell membrane, muscles move, etc.  without this source of energy, a cell will die. it will not be able to repair itself, defend against pathogens, etc.