Q.4 Write note on human placenta.
Answers
Answer:
The placenta is an ephemeral organ found only in eutherian mammals during gestation.
The placenta is the only organ composed of cells derived from two different organisms i.e. from the fetus and the mother.
The fetal membranes are chorion and amnion.
The membranes from the uterine wall are deciduas basalis. It is the portion of the deciduas which is directly adjacent to conception at the implantation site.
Decidua is a mucous membrane lining the uterus during pregnancy and it cast off during childbirth. After the implantation of the embryo, the uterine endometrium is called decidua.
Placenta weight is around 600 gm when fully formed, measures 20 cm in diameter and 3 cm thick at the center.
The placenta supplies oxygen and nutrients to the embryo and also removes carbon dioxide and excretory/waste materials produced by the embryo.
