(a) Name two male sex organs and two female sex organs which develop completely at puberty. (b) Name two things which may develop on the face of adolescent boys and girls during puberty due to the increased activity of sebaceous glands and sweat glands in the skin.

(a) In males, the two primary sex organs that develop completely at puberty are the testes and the penis. During childhood, these organs remain relatively small and immature. At puberty, rising testosterone levels cause significant growth and functional maturation. The testes enlarge substantially and begin producing viable sperm through spermatogenesis, while also increasing testosterone production. The penis increases in both length and girth, becoming capable of erection and ejaculation. In females, the two primary sex organs that fully develop at puberty are the ovaries and the uterus. The ovaries, which contain all the eggs a woman will ever have since before birth, begin to mature and release eggs through ovulation, typically on a monthly cycle. They also significantly increase production of estrogen and progesterone. The uterus grows considerably in size and develops a thick, hormone-responsive lining (endometrium) that builds up and sheds monthly during menstruation, preparing the body for potential pregnancy.

(b) Two common developments on the face of adolescent boys and girls caused by increased sebaceous and sweat gland activity are acne (pimples) and oily skin. Acne occurs when excess sebum (oil) produced by overactive sebaceous glands combines with dead skin cells to clog hair follicles and pores. Bacteria proliferate in these blocked pores, causing inflammation that appears as pimples, blackheads, whiteheads, or in severe cases, painful cysts and nodules. The face is particularly affected because it has a high concentration of sebaceous glands, especially in the T-zone (forehead, nose, and chin). Oily skin results from the same hormonal stimulation causing sebaceous glands to produce excessive sebum, giving the skin a shiny, greasy appearance that is especially noticeable on the forehead and nose. Boys typically experience more severe acne than girls due to higher androgen levels, though both sexes are affected. Additionally, increased sweat gland activity can contribute to these issues by adding moisture that, combined with oil and bacteria, creates an environment conducive to acne formation. Proper facial hygiene—gentle cleansing twice daily, avoiding touching the face with dirty hands, using oil-free products, and not picking at pimples—can help manage these conditions, though they often improve naturally as hormone levels stabilize in late adolescence.