Testosterone is the male sex hormone (as apposed to estrogen which is the female sex hormone). Both males and females have testosterone, though the males have a much larger quantity than females (just as women have more estrogen than men). It is primarily produced in the testis for men, and in the ovaries for women. Testosterone is made from andogens produced by the adrenal cortex. Higher levels of this hormone are associated with hair growth, muscle developement, and prominance of the "Adam's apple" or larynx.

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