Intro | Anterior Pituitary | Adrenal Glands | Ovaries | Pancreas | Posterior Pituitary | Testes | Thyroid

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The Testes are the male gonads, or reproductive glands. When stimulated by the release of pituitary gonadotropins, these glands produce and secrete the hormones that control the development of male sexual characteristics and the reproductive function of the adult male.


The testes produce and secrete testosterone in response to the release of follicle-stimulating hormone from the anterior pituitary. Testosterone and related hormones have both organizing and activating effects on physiology, anatomy, and psychology. The organizing effects of testosterone emerge during the third and fourth months of gestation (pregnancy). When testosterone is present in greater levels than the female sex hormone, the fetus will develop the characteristics of a male. Testosterone will modify the reproductive organs and regions of the central nervous system, including the hypothalamus. The activating effects of testosterone not only trigger sexual prowess and aggressiveness, but also modulate cerebral functions. Recent research indicates that fluctuating levels of estrogen and testosterone modify higher, problem-solving abilities.