1. Keratinocyte (Skin Cell) Number in the body: 2.2 million million Number an adult makes each minute: 55 million Length: 15 micrometers Number of functions: 2 Most adults have about 2.7kg of skin on their bodies. This is about the weight of five tins of baked beans.

2. Neurone (Brain Cell) Number in the body: 100 000 million Number an adult makes each minute: 0 Length: 120 micrometers Number of functions: 1 Human brains are clever because all the cells send electrical messages at fast speeds to each other. This means that all of the neurones can work together.

3. Neutrophil (White Blood Cell) Number in the body: 40 000 million Number an adult makes each minute: 7 million Length: 20 micrometers Number of functions: 2 Destroy viruses and bacteria. They take the microbes inside them and kill them with powerful chemicals.

4. Stem Cell Number in the body: 1 million million Number an adult makes each minute: Not know Length: 7 micrometers Number of functions: 1 Stem cells can become any type of cell in your body.

5. Sperm Cell Number in the body: 1555 million Number an adult makes each minute: 90 000 Length: 40 micrometers Number of functions: 1 Approximately 100 million to 300 million sperm cells are released at one time. The sperm can swim up to 20cm in an hour.

6. Oocyte (Egg Cell) Number in the body: 400 000 thousand Number an adult makes each minute: 0 Length: 100 micrometers Number of functions: 1 A women has more eggs than she can use in her lifetime. They are all made before she is born.

7. Adipocyte (Fat Cell) Number in the body: 40 000 million Number an adult makes each minute: 0 Length: 200 micrometers Number of functions: 5 Fat cells can grow up to ten times bigger by squeezing in more fat.

8. Erythrocytes (Red Blood Cell) Number in the body: 30 million million Number an adult makes each minute: 2 million Length: 7.5 micrometers Number of functions: 2 These cells lose their nucleus after they have been made so that that can pack in as much red haemoglobin as they can. Haemoglobin carries oxygen.