The energy a cell needs to build molecules or to power cellular respiration is supplied by

The energy a cell needs to build molecules or to power cellular respiration is supplied by mitochondria.

Explanation:

Mitochondria  are tiny cell organelle present in eukaryotic cells. It is called the powerhouse of the cell. It is referred to as such because it produces most number of energy molecules or ATP that is released from food. It produces 36 molecules of ATP and the cell produces 2 molecules of ATP. This process of releasing energy from food by the mitochondria is called cellular respiration. These energy molecules are then used in various other cellular activities.

wouldnt it be the scientific method?

explanation:

explanation:

b,bacteria convert nitrates

into nitrogen gas.

d,plants and animals take in

and use nitrogen compounds.

e,bacteria break down waste    

products and return nitrogen  

to the soil.

a,bacteria convert atmospheric

nitrogen to ammonia.

c,bacteria convert ammonia

to nitrites and nitrates.