Question

Describe menstrual cycle.

Answer 1

Menstrual cycle:

1. In females, every month either of the ovaries releases an egg for fertilization to take place.
2. The uterine wall thickens and prepares itself to implant the fertilized egg.
3. However, in the absence of fertilization the uterine wall breaks, and blood and mucous come out through the vaginal passage. This phenomenon is known as the menstrual cycle or menstruation.

Phases of the Menstrual Cycle:

1. Menstrual phase:
   • This phase starts on day 1 of the cycle during which the uterine wall breaks, and blood and mucous come out through the vaginal passage which lasts for about 3 to 5 days.
2. Follicular phase:
   • During the follicular phase the primary follicle matures to form the Graffian follicle.
   • Graffian follicle is a structure present inside the ovary which encloses the egg.
   • The endometrium ((uterine wall) also starts proliferating.
   • The uterus starts preparation for another pregnancy.
     
3. Ovulatory phase:
   • This is the mid-cycle phase, during which ovulation (release of eggs from the ovary) takes place.
   • The end of the follicular phase and period of ovulation period marks the fertilization period.
   • It occurs on the 13th to 17th days of the cycle.
     
4. Luteal phase:
   • It is also known as the post-ovulation phase.
   • During this phase, the fate of the corpus luteum is decided.
   • The Corpus luteum is formed by the ovarian follicle which has released its egg.
   • If fertilization takes place pregnancy begins and if it does not take place then a new menstruation cycle begins