Which of the following statements is incorrect. Human spermatozoa normally
At a concentration of $1$ million/ml of ejaculate will fertilize the ovum
Are released in large numbers after a few days abstinence
Contain enzyme in their head which helps in penetration of ovum
Move with the help of their tails
Function of gynogamone$-I$ is
The first movements of the foetus and appearance of hair on its head are usually observed during which month of pregnancy?
Sertoli's cell are regulated by the pituitary hormone known as
Mammalian eggs have
In mammals egg are microlecithal and isolecithal because these are