Correction, first it was villages than they joined together, also they expanded their land a lot. villages, to towns, citys, city states, than empires
The answer to the question is D
Answer:
Correct answer: Norepinephrine is a substance that is predominantly released from the ends of sympathetic nerve fibers.
Explanation:
Norepinephrine is a substance that is predominantly released from the ends of sympathetic nerve fibers and that activates the force of skeletal muscle contraction as well as the rate and force of contraction of the heart. Their actions are vital to the fight or flight response, so the body thus prepares to react or withdraw from an acute threat.
