Testosterone is responsible for secondary male characteristics, estradiol for secondary female characteristics and menstrual cycle control, and progesterone prepares the uterus for the implantation of a fertilized egg.

Malfunctioning adrenal cortex, as seen in Addison’s disease, leads to hypoglycemia, weakness, and increased stress susceptibility. Treatment involves glucocorticoids and mineralocorticoids.

Glucocorticoids control carbohydrate metabolism, modulate inflammatory reactions, and respond to stress, while mineralocorticoids regulate water and salt excretion by the kidneys.

Hormones act as intercellular messengers, and they vary in chemical nature. Examples include steroids (estrogens, androgens), polypeptides (insulin, endorphins), and amino acid derivatives (epinephrine, norepinephrine). Hormones help maintain biological balance, as seen in insulin and glucagon regulating blood glucose levels.