12. when looking at alleles and how they are passed from parents to offspring, the combination of alleles (such as tt or tt) is called the organism's .
a. phenotype
b. genotype
c. protein inheritance
d. dna

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.