State the changes that take place in the uterus when:
(i) Implantation of embryo has occurred.
(ii) Female gamete/egg is not fertilised.
- a disc-like special tissue develops between the uterus wall and the embryo called the placenta.
- It is through the placenta that all the requirements of the developing foetus like nutrition, respiration, excretion, etc are met from the mother’s body.
If the female gamete is not fertilised,
- then the thick and spongy uterus lining is not required.
- So, this breaks down and comes through the vagina as blood and mucus ie., menstruation occurs.