Gonads

 Gonads 

Gonads are testes in male and overies in female.

Both of these organs produce and secrete hormones that are balanced by hypothalamus and pituitary gland. 

Gonads produce steroids sex hormone.

1. Female sex hormone

Estrogens and progesterone

1. Estrogens

Responsible for maturation of reproductive organs and appearance of secondary sex characteristics of females.

Estrogen increases at time of puberty and causes growth of uterus and vagina.

Estrogen and progesterone are responsible for development of breast and for uterine cycle (menstrual cycle).

2. Progesterone

Progesterone in female hormone secreted by corpus luteum after ovulation during second half of menstrual cycle.

It helps prepare body for conception and pregnancy and regulates monthly menstrual cycle.

Progesterone prepares lining of uterus.

3. Inhibin 

Corpus luteum is made from follicle that houses maturing egg.

Follicle and corpus luteum in overy also secrete inhibin.

This is the hormone that decreases FSH (follicle stimulating hormone) production.

By means negative feedback inhibition of anterior pituitary.

2. Male sex hormone 

Testosterone

Testosterone belongs to family of androgen, which are steroid hormones producing masculine effects.

During puberty testosterone initiates maturation of male reproductive organ and appearance of secondary sex characteristics (Hair growth on face and deep pitch of voice).

Testosterone is necessary for normal sperm production and maintain reproductive organs, functional state in adult males.

Testosterone increases protein production.

Hormones that build up protein are called anabolic steroids.

2. Inhibin 

Sustentacular cells of testes secret inhibin, which decreases FSH secretion.

Regulation of Secretion

Release of gonadal hormone is regulated by Gonadotropins of anterior pituitary gland.