In human females, each time during maturation and release of egg, the inner wall of uterus thickens. Is this thickening permanent? Give reasons.
Answer variants:
Thickened lining shed only after pregnancy
Thickened lining shed during pregnancy
If not fertilized, the egg and thickened lining are shed during menstruation
No, it is not permanent.
If not fertilized, the egg and thickened lining are shed during menopause.
Yes, it is permanent.