Protein

Key Stage 3

Proteins are molecules in our diet that are used by our bodies for growth and repair.

There are many different proteins.

Protein is used to build muscles and repair injuries.

Not enough protein can cause a disease called Kwashiorkor.

We can eat any of these foods to get enough protein.

Meat provides lots of protein for a balanced diet.	You can help keep your diet balanced by eating lots of different beans.	Nuts are the seeds of trees and are part of a balanced diet.	There are many different kinds of peas that can help make sure you have a balanced diet.

Adding protein to Biuret solution will cause the solution to turn purple.

1. Take a small sample of food and dissolve it in water.

2. Add some Biuret to the solution.

3. If it turns from blue to purple then the food contained protein.


This Biuret has turned purple, indicating protein is present.

Proteins, also known as polypeptides, are large polymer molecules made from amino acids that are used by our bodies for growth and repair.

Proteins are broken down by our digestive systems into amino acids which are then transported around the body by our blood.

Cells build new proteins from amino acids in a process called protein synthesis which takes place at the ribosomes in cells.

Protein is essential to build enzymes which control the metabolic processes inside the cell.

A single protein can be made of millions of amino acids bonded together.


This diagram shows an amino acid and a small protein made of 3 different amino acids.