Define the following processes:
$(a)$ Fertilization
$(b)$ Menstruation
$(c)$ Binary fission
$(d)$ Vegetative propagation
$(e)$ Regeneration

(N/A) The fusion of a male gamete with a female gamete is known as fertilization.
$(b)$ The cycle that occurs every month when an egg is not fertilized is known as menstruation. It lasts for about $2$ to $8$ days,during which the lining of the uterus slowly breaks down and is discharged through the vagina as blood and mucus.
$(c)$ The splitting of a parent cell into two daughter cells,which can occur in any plane,is known as binary fission. It is observed in organisms like $Amoeba$.
$(d)$ When a vegetative part of a plant,such as the root,stem,or leaves,develops into a new plant under appropriate conditions,it is known as vegetative propagation.
$(e)$ When the body of an organism is cut into any number of pieces and each piece grows into a complete organism,this is known as regeneration. It is observed in $Hydra$ and $Planaria$.