With the following crosses of pea plants, give the flower color of offspring and the ratio expected (blue is dominant).

a cross of blue x blue (both heterozygous) would result in

all blue
all white
3 blue, 1 white
2 blue, 2 white

The answer would be abrasion.

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.