Question

What is placenta? Explain how it is formed.

Answer 1

Placenta:

1. The placenta is a transient union of the fetal membrane and the material tissues.
2. Through the umbilical cord, it provides nutritional support to the growing embryo.
3. It includes blood arteries that link the placenta to the uterus and provide nourishment and $O_2$ supply to the developing embryo or baby.
4. The placenta permits waste products such as urea, $C{O}_2$, and other waste materials to diffuse into the mother's body for disposal.
5. The placenta functions as an endocrine gland as well.
6. It generates hormones such as estrogen and progesterone.

Its formation:

1. The development of the placenta begins with the blastocyst's implantation.
2. The outer trophoblast cells and the inner cell mass are two separate differentiated embryonic cell types found in the $32-64$ cell blastocyst.
3. The placenta is made up of trophoblast cells.