Hormones regulate both the male and female reproductive systems. the principal male sex hormone is testosterone and is produced in the testes. secretion of testosterone increases sharply at puberty and is responsible for the development of secondary sexual characteristics of men and is essential for the production of sperm. sexually mature females secrete a mixture of estrogens and progesterone, both of which are produced in the a) brain b) uterus c) ovaries d) fallopian tubes