Describe menstrual cycle in human beings. Add a note on its hormonal control.
Answers
Menstrual cycle- The menstrual cycle is a term used to describe monthly events that occur within a woman's body in preparation for the possibility of pregnancy. Each month, an egg is released from an ovary in a process called ovulation. ... The menstrual cycle is under control of hormones secreted by the pituitary gland and the ovaries.
The hormone oestrogen is secreted by the ovaries. Oestrogen makes two things happen: it stops FSH being produced - so that only one egg matures in a cycle. it stimulates the pituitary gland to release luteinizing hormone (LH), which triggers ovulation (the release of the mature egg from the ovary).
Explanation:
A concurrent series of changes that occur in the endometrium of the uterus to prepare it for the arrival of a fertilise ovum that would develop into a young one. If fertilisation fails to occur then the stratum functionalis of the endometrium sloughsoff. This is a cycle that completes in twenty eight days and is termed as menstrual cycle.
The menstrual cycle is divided in to four phases and are dependent on the different hormonal control, The first phase is the follicular phase, in which the primary follicle develops into Graafian follicle under the control of FSH. Then the follicular cells of the Graafian follicle secrete estrogen that stimulates the thickening of the endometrium and inhibits secretion of FSH and stimulates the secretion of Lutenising hormone (LH).ON the 15th day the ovulatory phase begins and the Graafian follicle ruptures to release ovum. The process of ovulation is controlled by LH which also controls the change of empty Graafian follicle into the corpus leuteum.Corpus leuteum secretes progesterone this promotes further endometrial proliferation and prepares it for implantation. If fertilisation fails to occur the hormonal level falls and the endometrial lining sloughs off.