Answer: Serotonin
Explanation:
Serotonin is an hormone, derived from the amino acid, tryptothan. It is involved in vasodilation, sleep regulation, mood changes, capillary permeability, and causes contraction of smooth muscles like that of the stomach to signal hunger.
Answer:
d
the correct answers are digestive,sensory,and nervous system
I added a pic idk if u can view but it verifies the answers hope it helps
c
an Individuals chromosomes, and homologous pairs?