Adenine, thymine, guanine, and cytosine
Answer:
A. motor neurons; peripheral nervous system
Explanation:
Motor neurons carry signals from the peripheral nervous system to the muscles. This causes the muscles to either relax or contract. Note that the peripheral nervous system consists of neurons and parts of neurons outside of the central nervous system which consists of the brain and spinal cord. When signals are transmitted between the motor neurons and peripheral nervous system, this causes a response to stimulus in the muscles which would either, relax or contract.
limbic system
Explanation:
center of emotional processing is the amygdala
D. Homeostasis- naturally selected function
