C. Females show cyclically in secretion of hormones and their major class is estrogens. Called estrous cycle in rats, menstrual cycle in humans. Estrogen and progesterone is produced by ovaries. GnRH released from hypothalamus acts on Pituitary to release LH and FSH b. LH and FSH are gonadotropin and stimulate estrogen and ovulation c. E and FSH rise in the preovulatory phase, then there is a surge in LH at mid cycle, which triggers ovulation and progesterone release.
Progesterone falls and cycle restarts.
Sexual orientation A. Male homosexuality is not rare. It occur in many other mammalian species 1. Homo and hetero have the same level of circulating hormone. What is the selective pressure, homosexual coitus does not lead to reproduction. F. Used to be thought that psychological factors caused homosexuality.