Question

What is the difference between pinocytosis and phagocytosis?

Answer 1

Hint:- In Pinocytosis, intake of smaller substances such as solute takes place in the cells while in Phagocytosis, larger substances such as bacteria ingested into the cell by the process of ingestion. Pinocytosis is also known as cell drinking while Phagocytosis is known as cell eating. Pinocytosis occurs in almost every cell of the body while Phagocytosis takes place in immune cells.

Complete answer:
Ingestion or endocytosis of liquid droplets occurs in the cell by forming vesicles. Vesicles are formed by the invagination and pinching off the cell membrane. These are known as endosomes formed during endocytosis.
In pinocytosis, vesicles are formed at the plasma membrane, and bring fluids, small molecules into the cell. This process is often called cell drinking.
Examples: once the vesicle is inside the cytoplasm, water and small molecules enter the cell across the vesicle membrane.
In phagocytosis, vesicles form at plasma membranes to bring solid particles into the cell. This process is often called cell eating. Presence of pathogens and cellular debris offsets the rate of phagocytosis. Bacteria, viruses, cellular debris and other foreign material are the substances involved in this process.
Example: Large particles brought into a cell by cytoplasmic extensions called pseudopodia that engulf the particles and pull it into the cells.
In phagocytosis, exocytosis occurs at the end while it does not occur in pinocytosis.
Receptors include phagocytosis while pinocytosis is a continuous process.

Note:- Exocytosis and endocytosis are the other processes occurring in the cell for engulfing other substances. Phagocytosis and pinocytosis both are active processes that means they require energy (ATP) as adenosine triphosphate for the uptake of materials. These processes play an important role in the functioning of cells.