Write true or false for the statement: If the egg is not fertilized,it lives for about one day.

Explain what happens when:
$(a)$ Testosterone is released in males.
$(b)$ Pollen grain falls on the stigma of the flower.
$(c)$ Egg fuses with sperm cell.
$(d)$ Planaria is cut into many pieces.
$(e)$ Buds are formed on the notches of the Bryophyllum leaf.

At what age do girls typically reach puberty (in $years$)?

Name two simple organisms having the ability of regeneration.

Characters transmitted from parents to offspring are present in

Can you consider cell division as a type of reproduction in unicellular organisms? Give one reason.