The cleavage in the human zygote is.....

Which chemical present in the ovum attracts the sperm?

After implantation,finger-like projections on the trophoblast are called $...A....$ which are surrounded by $...B..$ and maternal blood. Here $A$ and $B$ refers to

What helps in the penetration of the egg by the sperm?

Ectopic pregnancies are referred to as

During cleavage,the zygote undergoes mitotic division as it moves through the .... of the oviduct.