Biology – Mode of action of enzymes | e-Consult

Intracellular enzymes are enzymes produced and used within the cells of an organism. They catalyze reactions that occur within the cellular environment. Extracellular enzymes are enzymes that are secreted by cells and function outside the cell, in the surrounding environment.

Examples of intracellular enzymes include amylase (which breaks down starch in the cytoplasm), DNA polymerase (involved in DNA replication within the nucleus), and various enzymes involved in metabolic pathways within the mitochondria.

Examples of extracellular enzymes include digestive enzymes like pepsin (in the stomach), amylase (in the salivary glands and pancreas), and trypsin (in the pancreas).

Advantages of intracellular enzymes:

• They are readily available to catalyze reactions within the cell.
• They are protected from harsh environmental conditions.
• They can be regulated by intracellular signaling pathways.

Advantages of extracellular enzymes:

• They can act on substrates that are outside the cell.
• They can be secreted in large quantities to efficiently digest food or perform other extracellular functions.
• They can be regulated by hormonal signals.