In the early haemopoietic tissue of the embryo,there is:

Which of the following is $NOT$ true for gastrulation?

$A$: Human chorionic gonadotrophin $(hCG)$ prevents the corpus luteum from involuting.
$R$: It has properties similar to luteinizing hormone $(LH)$.

Blastopore is found in

Which hormone is produced by the placenta?

During the fourth and sixth cleavage of the zygote in sea urchin development,what is the fate of the resulting cells?