Acetylcholine (ACh)
Acetylcholine is an organic chemical that functions in the brain and body of many types of animals as a neurotransmitter.
These primates have retained some primitive mammalian anatomical and behavioral traits, such as a strong sense of smell with an associated longer snout, eyes that are positioned more to the sides of the head, a smaller brain, a distinct breeding season and litters of offspring, nocturnal activity and the ability to synthesis vitamin C.
Each part at apart of the plant
I don't know how specific you need to get for this question. The basic answer would be the mitochondria as it is where the Krebs Cycle, the Electron Transport Chain, and Chemiosmosis (also referred to as oxidative phosphorylation) all occur. Chemiosmosis is where the majority of ATP is produced during cellular respiration, and it primarily occurs in the matrix of the mitochondria as protons move down the gradient through ATP Synthetase channels.