The best definition of the process of gastrulation is that, it is a process where the
Single layered blastula becomes two layered
Archenteron is formed
Cells move to occupy their definite position
Zygote gets converted to a larva
In humans, at the end of the first meiotic division, the male germ cells differentiate into the
How many cleavages are completed in $16$ celled stage of egg.
The breakage of the membrane surrounding the acrosome in a mammalian sperm is
How many chromosome numbers are present in primary spermatocytes of human ?
Foetal ejection reflex in human female is induced by