The persistence of corpus luteum during pregnancy is due to a hormone known as
Chorionic gonadotropic hormone
$FSH$
Estrogen
Progesterone
In Human beings, at the end of $12$ weeks (first trimester) of pregnancy, the following is observed
By the end of about .......... weeks, the body is covered with fine hair.
During the course of development, cells in various regions of embryo become variable in morphology and eventually perform diverse functions. This process is known as
During the development of embryo which of the following occur first
The extra structure that provides nutrition to the embryo is