The autonomic nervous system (ANS) is the part of the nervous system which is involuntary. It is composed of neurons that is responsible for impulsing the central nervous system to muscles and glands. The hypothalamus is the most important part and main control center of ANS. It is responsible for many homeostatic processes inside our body. Both the autonomic function and the endocrine function is regulated by the hypothalamus.
One half-life after a radioactive isotope is incorporated into a rock there will be only half of the original radioactive parent atoms remaining and an equal number of daughter atoms will have been produced.