Amniotic fluid protects the foetus from

Give the name of two hormones $A$ and $B$ in the figure given below

$A$ : Oxytocin acts on the uterine muscles and cause stronger uterine contractions, which in turn stimulates further secretion of oxytocin.
$R$ : Oxytocin is released from maternal pituitary

As a result of cleavages, if blastomeres are symmetrically placed around the polar axis the type of cleavage is known as

Prepuberal period refers to a stage of

Cowper's gland is present in