In rabbit, man and other placental mammals the organ in which fertilization of ovum is,

Polar bodies are produced during the formation of

Beginning of archenteron formation in frog's development represents the stage of

The middle piece of the sperm contains

The gestation period of elephant is about

Which of the following cells present in mammalian tests help to nourish sperms?

The most fundamental characteristic of living being is

The preparation of sperm, before penetration into ovum, is called

Meroblastic cleavage refers to which type of division of eggs?

Prostate gland secretion helps in the formation of