Science
What is a Protein?
A protein is a large molecule made of building blocks called amino acids, folded into a specific shape that lets it do a job in living things. Proteins build and repair tissue, speed up reactions (as enzymes), carry oxygen, fight infection, and much more — they're the workhorses of every cell.
See it, don’t just read it.
Watch a 2-minute lesson with voice + animation that explains a protein.
Key things to understand
- 1Proteins are long chains of amino acids folded into precise 3D shapes.
- 2Your DNA carries the instructions for which amino acids to string together to make each protein.
- 3They do almost every job in the body: enzymes (speed reactions), antibodies (fight germs), haemoglobin (carries oxygen), muscle fibres, and more.
- 4There are 20 amino acids; the order and folding determine what a protein does.
- 5We get the amino acids to build them from protein in food — meat, beans, eggs, dairy.
Frequently asked questions
- What are proteins made of?
- Amino acids — small molecules linked in a chain. There are 20 kinds, and their sequence (set by your DNA) folds into the protein's working shape.
- What do proteins do in the body?
- Almost everything: they form muscle and tissue, act as enzymes that speed up reactions, carry oxygen, make antibodies, and send signals as hormones.
- Why do we need protein in our diet?
- Food protein is broken down into amino acids, which your body reuses to build its own proteins for growth, repair, and countless functions.