What is an enzyme?

An enzyme is a type of protein that catalyses reactions that occur in the body. In many cases they are essential in order to allow reactions to occur under physiological conditions. There are many different types of enzymes, for example digestive enzymes break down carbohydrates, fats and proteins in the digestive system. Other enzymes are involved in the formation of molecules like DNA. 

RA

Related Biology GCSE answers

All answers ▸

What molecules are proteins made of? (1 mark)


Explain the main thermoregulatory processes in humans.


Emphysema is a disease affecting the lungs. People with emphysema are often short of breath and find exercise difficult. Explain what happens to the lungs in this disease to cause the symptoms mentioned.


What are the differences between diffusion, osmosis and active transport?