Unlike the female sex glands, ovaries, the testes are located outside of the body in the scrotum. This is to achieve temperature regulation necessary for optimal sperm production, as normal body temperature is too warm for this. As the testicular temperature drops, the testes are drawn closer to the body for additional warmth. As the testicular temperature increases, the testes lower away from the body in order to cool off.
The testes are a part of the endocrine system, a network in the body that releases hormones into the bloodstream. The hormones released by the testes allows the individual to mature through their physical appearance, thoughts, and behavior.
The testes release sex hormones called androgens, while the ovaries produce hormones called estrogens, mainly "estradiol." Within the class of androgens, a hormone called "testosterone" increases about 20 times the level it was before puberty. Though both males and females have estrogen and androgens, it is the increase of estradiol in girls and testosterone in boys that causes the first physical changes during puberty, which are known as "secondary sex characteristics."
- Wile, Dr. Jay L. Exploring Creation With Biology. Apologia Educational Ministries, Inc. 1998
- Grison, Sarah, and Michael S. Gazzaniga. Psychology in Your Life. W.W. Norton & Company, Inc., 2017.
- Roche & Sun, 2003