Define the following terms:
$(i)$ Endocytosis
$(ii)$ Phagocytosis
$(iii)$ Exocytosis

(N/A) $(i)$ Endocytosis: It is the process of ingestion of material by the cells through the plasma membrane.
$(ii)$ Phagocytosis: It is a common method of feeding in some organisms such as $Amoeba$ and sponges. Biologically, it means "cell eating". The $WBCs$ engulf cell debris and microbes with the help of this process.
$(iii)$ Exocytosis: It is the process by which the plasma membrane removes its contents to the surrounding medium.