All reactions occurring inside cells require raw materials such as substrates to make the compulsory products needed by the organism. The raw materials need to be constantly supplied to the cells as the organism will always be in demand for the products. The nutrients come from the organisms diet and they are orient found in the form of polymers, proteins and polysaccharides would be an example. These large molecules cannot enter the cell straight away, they must be broken down into smaller molecules before being able to pass through the cell- surface membrane. (Extracellular) Enzymes are released from the cells to break down these large molecules into smaller ones to help aid processes like digestion.

Most extracellular enzymes work outside the cell they were made in but in other organisms such as fungi they work outside the body. Other single celled organisms such as bacteria and yeast release enzymes into their immediate environment, they then break down the larger molecules like proteins into smaller molecules like amino acids that will then be absorbed by cells.

Single celled and multicellular organisms count on extracellular enzymes to utilise polymers for nutrition.

A lot of multicellular organisms eat food to gain the nutrients required for thing like growth and repair inside the body, once the larger molecules have been broken down, the smaller molecules can be absorbed into the bloodstream and transported around the body to all the necessary areas, they can also be used as substrates in cellular reactions.

Examples of extracellular enzymes that are involved in digestion in humans are analyse and trypsin.

	Created by molly skinner over 6 years ago

A level Biology Note on Extracellular enzymes notes; in detail, created by molly skinner on 14/03/2018.