Testes - Ovaries and Male-Female sex Hormones

Testes and Ovaries 
The sex organs are the testes, located in the male scrotum, and the ovaries, located in the female pelvic cavity. The testes produce the androgens (for example, testosterone), which are the male sex hormones, and the ovaries produce estrogen and progesterone, the female sex hormones. The hypothalamus and pituitary gland control the hormonal secretions of these organs in the same manner as described for the thy­roid gland.
Testosterone 
The male sex hormone, testosterone, is essential for the normal development and functioning of the male sex or­gans. It is also necessary for the maturation of sperm.
Greatly increased testosterone secretion at the time of puberty stimulates the growth of the penis and the testes. Testosterone also brings about and maintains the male sec­ondary sex characteristics that develop at the time of pu­berty, such as a beard, axillary (underarm) hair, and pubic hair. It prompts the larynx and vocal cords to enlarge, caus­ing the voice to change. Testosterone is responsible for the greater muscular strength of males, which is why some ath­letes take supplemental amounts of anabolic steroids, which are either testosterone or similar chemicals. But testos­terone also promotes closure of the epiphyses of long bones and therefore stops growth. Testosterone also causes sebaceous and sweat glands in the skin to secrete; therefore, it is largely respon­sible for acne and body odor. Another effect of testosterone activity is pattern baldness. Genes for baldness probably are inherited by both sexes, but baldness is seen more often in males because of the presence of testosterone.
Testosterone is believed to be largely responsible for the sex drive. It may even contribute to the supposed ag­gressiveness of males.
Estrogen and Progesterone 
The female sex hormones, estrogen and progesterone, have many effects on the body. In particular, estrogen secreted a the time of puberty stimulates the growth of the uterus and the vagina. Estrogen is necessary for egg maturation and is largely responsible for female secondary sex characteristics, such as female body hair and fat distribution. In general, fe­males have a more rounded appearance than males because of a greater accumulation of fat beneath the skin. Also, the pelvic girdle enlarges in females so that the pelvic cavity has a larger relative size compared to males; this means that fe­males have wider hips. Estrogen also promotes closure of the epiphyses of long bones and therefore stops growth. Both es­trogen and progesterone are also required for breast develop­ment and regulation of the uterine cycle, which includes monthly menstruation (discharge of blood from the uterus).
The androgens, primarily testosterone, are the male sex hormones produced by the testes. Estrogen and progesterone are the female sex hormones produced by the ovaries. The sex hormones maintain the sex organs and the secondary sex characteristics.

Posted in Human Anatomy and Physiology