The mitochondrion functions in the ATP synthesis.
Step-by-step explanation:
Mitochondria helps in formation of ATP molecule with the help of the membrane bound protein known as ATP synthase. These proteins catalyzes the addition of phosphate group to the adenosine nucleotide and then add phosphate group to the previously attached phosphate group by producing a phosphoanhydride bonds. These phosphoanhydride Bond releases high energy in the system when broken. The third phosphate from adenosine releases the maximum energy followed by the the others.