Answer:
A. a protein
Explanation:
Proteins function as enzymes in most of the catalyzing reactions, that increases the rate of reaction within cell.
Proteins are consist of multiple numbers of amino acids and the twisting and folding amino acids provide a unique identity to enzymes. Not all the proteins are enzymes but all the enzymes are proteins.
For example: Trypsin, Pepsin, and Lipases.
Hence, the correct option is "A. a protein".
It was also found that an increase in testosterone during the PASP predicted subsequent willingness to choose competitive tasks (3, 28, 29). ... Aggression research in human studies has revealed an interesting property of testosterone dynamics, its rapid fluctuations provoking reactive aggression in response to stimuli.
Answer;
Vesicles containing neurotransmitter.
Explanation;
-Neurotransmitters are released by secretion from the ends of axonal terminals.
-Synaptic vesicles store various neurotransmitters that are released at the synapse.
-Neurotransmitters are released from the axon terminal when their vesicles "fuse" with the membrane of the axon terminal, spilling the neurotransmitter into the synaptic cleft.
Activation energy ........