Question

Describe the role of pituitary and ovarian hormones in the menstrual cycle of human females.

Answer 1

Hint: The Pituitary gland is the master endocrine gland. This means it controls all the other endocrine glands of the body. Gonads are heterocrine glands (mixed or composite). Thus the endocrine secretions of these glands are also controlled by the pituitary. The Pituitary gland, in turn, is controlled by hypothalamus. Thus the hypothalamus is the master of the master endocrine gland.

Complete answer:
Lets understand this by the table given below.

Let us understand the above chart
As mentioned, The hypothalamus secretes Releasing hormones which causes release of Gonadotropins from anterior pituitary. These Gonadotropins are FSH (Follicle stimulating hormone) and LH (Luteinizing hormone). These two have a major role to control the ovarian hormones (Estrogen and Progesterone). FSH is responsible for formation and maturation of follicles. Mature follicles release Estrogen. This hormone helps in the further maturation of the follicles and also begins the repair of Endometrium as follicle formation begins after Menstruation and thus repair is important. The mature follicle further undergoes ovulation. This is under the influence of LH. After ovulation the mature follicle becomes corpus luteum and the oocyte enters the oviduct so that it can get fertilised in case the sperm arrives. The corpus luteum releases Progesterone and estrogen. These hormones maintain the endometrium. This is very important because if the sperm arrives and fertilisation takes place, the uterus should be ready for implantation and hence progesterone and estrogen causes release of many secretory glands from the uterus.

Thus every stage of menstrual cycle is maintained by pituitary and ovarian hormones.

Note: Menstrual cycle shows changes inside the ovary and the uterus simultaneously. Both these changes are controlled by ovarian hormones. These hormones also control the secondary sexual characters in a female. Estrogen also controls the cholesterol level in females and so you all must have heard that heart problems are more common in males than females. Now i hope the reason for it is clear.