PLEASE HURRY... Which of the following is a limitation of models?

a They are smaller than the thing they model.

b They are large enough to be seen.

c They use familiar things to model unfamiliar things.

d They do not act exactly like the thing they model.

Atissue is a group of connected cells that have a similar function within an organism.

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.