In human males,the testes lie in the scrotum,because it helps in the

Where are the testes located in human males?

Give the respective scientific terms used for studying:
$(i)$ The mechanism by which variations are created and inherited,and
$(ii)$ The development of new types of organisms from existing ones.

In human females,an event that reflects the onset of the reproductive phase is

In a flower, the parts that produce male and female gametes (germ cells) are

In the given figure,label the parts and mention their functions:
$(a)$ Production of egg
$(b)$ Site of fertilisation
$(c)$ Site of implantation
$(d)$ Entry of the sperms