Helping to maintain a person's set point, the body's fat cells produce a hormone called __________ in amounts proportional to the total amount of fat.

A) leptin
B) dopamine
C) thoracin
D) human chorionic gonadotropin (HCG)

Leptin

A hormone produced by fat cells that helps to regulate body weight by signaling the brain to reduce appetite and increase energy expenditure.

Human Chorionic Gonadotropin

A hormone produced during pregnancy that supports the normal development of an egg in a woman's ovary, and stimulates the release of the egg during ovulation.