|MadSci Network: Genetics|
One cannot neglect the effect of the sex hormones on temperament. There is no doubt that “testosterone” promotes aggressiveness and that “estrogen” is associated with a milder temperament. “Testosterone” secreted by the male testes has a powerful anabolic effect in causing greatly increased deposition of protein everywhere in the body, especially in the muscles. In fact, even the man who participates in very little sport activity but who nevertheless is well endowed with testosterone will have muscle that grow to sizes 40 percent or more greater than those of his female counterpart and with a corresponding increase in strength. The female sex hormone “estrogen” probably also accounts for some of the difference between female and male performance, although not nearly so much as testosterone. “Estrogen” is known to increase the deposition of fat in the female, especially in certain tissues such as breasts, hips and subcutaneous tissues. REFERENCE :- GUYTON & HALL (MEDICAL PHYSIOLOGY) UNIT 15 , CHAPTER 84
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