The gonads (endocrine glands - testes and ovaries) produce sex hormones that stimulate reproductive organs and bring about sex characteristics.
Testes produce testosterone (Male sex hormone) and ovaries produce estrogen and progesterone (Female sex hormone).
The Luteinizing Hormone (LH) and Follicle-stimulating Hormone (FSH) stimulate secretion of sex hormones from the gonads.
The sex hormones are steroids synthesized from cholesterol.
During adolescence, high levels of sex hormones increase the activity of the oil glands and regulate body changes.
These hormones trigger bone remodeling that help in shaping the female pelvic girdle to adapt her for pregnancy and child birth.