What is an enzyme? And what things can affect them?

An enzyme is a substance produced by a living organism than enables reactions to happen faster or more efficiently.

Each enzyme has a specific shape called an active site which a certain molecule can fit into. Only one type of molecule can fit into the active site of that particular enzyme. This is called the hand and glove model- only certain hands will fit in certain gloves.

Once the molecule is in the enzyme's active site, the enzyme breaks down the molecule. Without the enzyme, this may not be able to happen or a very high temperature may be needed.

Enzymes can be damaged by high temperatures or pH levels. When an enzyme is damaged in this way it is said to have been denatured and the shape of the active site is changed so that the molecules can no longer fit in and be broken down.