Androgens induce the following changes in boys at the time of puberty. Penis enlarges in length and width. Scrotum becomes pigmented and wrinkled. Seminal vesicles, prostate and Cowper's glands enlarge and secrete. Larynx enlarges, vocal cords increase in length and thickness causing the voice to become deeper.
Hair appears in arm pits, on chest, and around anus.
General body hair increases. Behaviorally becomes more aggressive, active. Interest in the opposite sex develops. Sebaceous gland secretion thickens and increases predisposing to acne . Steroid Feedback Testosterone inhibits LH secretion by acting directly on the anterior pituitary and by inhibiting the secretion of hypothalamic GnRH .