In the adrenergic synapse, the neurotransmitter is norepinephrine. Adrenergic synapses release the neurotransmitter in the Sympathetic nervous system. This system controls reactions related to Increase brain activity and alertness, Dilation of the pupils, Crystalline accommodation for distance vision, Increased Respiratory and Cardiac Frequency, Vasodilation in the muscles of the legs, Reduction of salivary secretion, gastric and intestinal.
A person can only show a recessive trait if both of their parents carried at least one copy of each of the recessive allele. The parents do not need to show the trait, as one copy is not enough to reveal it, but they must both carry it.