Question

What happens to the lining of uterus?

(i) Before release of a fertilized egg?

(ii) If no fertilization occurs?​

Answer 1

Answer:

The fertilized egg attaches to the lining of the uterus. The placenta then develops. The placenta transfers nutrition and oxygen to the fetus from mother. If the egg does not become fertilized, the lining of the uterus (endometrium) is shed during menstruation.

i)Before release of egg the uterus prepares itself to receive the egg and makes a thick and soft lining of blood capillaries. It the egg does not get fertilized then after 28 days the lining breaks down and comes out through vagina in the form of blood.

ii)If the egg does not become fertilized, the lining of the uterus (endometrium) is shed during menstruation. The average menstrual cycle lasts 28 days. The cycle starts with the first day of one period and ends with the first day of the next period.