When an embryo develops inside the body of the female but does not obtain nutrients directly from the mother,the condition is known as:

Which one of the following is $NOT$ secreted by the corpus luteum?

Given below are two statements with respect to gastrulation.
$Statement-I$: Root of amniotic cavity is lined by amniogenic cells, which divides to form chorion.
$Statement-II$: Chorion is an embryonic membrane that participates in development of the embryo.
Choose the most appropriate answer from the options given below.

Placenta is the region where:

The foetus develops its limbs and digits in . . . . . . during embryonic development.

Corpus luteum is the source of secretion of