overview of gonads

what are the gonads

• ovaries in females

• testes in men

what are the 2 main functions of the gonads

• production of germ cells (ova or sperm)

• production of steroid sex hormones

why are sex hormones important

• necessary for normal development and function of reproductive organs

• differentiation of secondary sex characteristics

• plays role in pregnancy, childbirth and lactation

what are the 3 types of sex hormones

• androgens

• oestrogens

• progestogens

what are androgens and give an example

• androgens = male sex hormones

• e.g. testosterone

what are oestrogens and give an example

• oestrogen = female sex hormones

• e.g. 17β-oestradiol

what are progestogens and give an example

• progestogens = female sex hormones

• e.g. postesterone

what are the main effects (female or male) of androgens and oestrogens

• Androgens exert masculinising effects

• Oestrogens exert feminising effects

what is the main role of progestogens

mainly affects uterus in preparation for and during pregnancy

how does sperm and testosterone production occur in males

testes continuously produce spermatozoa and testosterone from puberty to old age

how does ovum and hormone production occur in adult females

usually one ovum is produced approximately every 28 days, with cyclical secretion of oestrogen and progesterone (menstrual cycle)

what happens at menopause

menstrual cycle and cyclical hormone secretion stop

what controls gonadal function and sexual activity

hypothalamus and anterior pituitary, under the influence of higher brain centres (cortex)