How proteins exist in living things
Extra knowledge
"Protein" is not the name of a single substance. It is the name of a large family that includes thousands of different substances. Here are a few members of that family you can recognise.
In animals
| Protein | Where it is found | What it does |
|---|---|---|
| Myosin and actin | Muscles | Let the muscle contract and relax again |
| Ossein | Bones | Gives bone flexibility so that it does not break easily |
| Haemoglobin | Red blood cells | Carries oxygen from the lungs all around the body |
| Keratin | Hair, fur, nails, bird feathers | Builds strong, protective coverings |
| Albumin | Egg white | Supplies food to the embryo growing inside the egg |
In plants
| Protein | Where it is found | What it does |
|---|---|---|
| Legumin | Pulse crops (such as mung bean and cowpea) | Stores protein inside the seed |
| Gluten | Wheat | Makes dough stretchy and sticky when flour is kneaded |