Key points
- Cells get the energy they need from glucose during respirationA chemical reaction that occurs in the mitochondria of cells in which glucose and oxygen react to produce carbon dioxide and water, releasing energy..
- Glucose is made by digesting carbohydrates These are mainly sugar and starches which provide your body with energy. Foods like bread, pasta, rice and potatoes contain lots of carbohydrates..
- Blood sugar level is the amount of glucose in one litre of blood.
Game - testing for sugar
Play an Atomic Labs experiment to find the sugar content of different foods.
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Video - Glucose in the body
A case study video explaining what role glucose plays in the body.
If you're an athlete, you'll need to take on more glucose than an ordinary person because you need the higher amount of energy.
Glucose is a sugar, which is a carbohydrate. When you see athletes taking on energy drinks and eating food, that's them replenishing the glucose in the body. The types of food and drinks that are good for glucose for athletes would be things like pastas, rices, bananas, oranges and energy drinks.
So, as a normal person when you take on the glucose, you probably find yourself feeling a little bit of a kick. You'll start to feel a little bit more energised - you're more able to carry on.
Why is glucose important?
You need energy for everything you do. Your cells get this energy from chemical reactions of glucose.
Glucose is a molecule with the chemical formula, C₆H₁₂O₆. A molecule of glucose contains carbon, hydrogen and oxygen atoms.
A model of the atoms found in a molecule of glucose.
Sources of glucose
Foods like bread, pasta and rice contain carbohydrates, which are your main source of energy. Digestion breaks down these carbohydrates, making glucose.
Many sweet foods, and energy drinks, already contain glucose. They make you feel energetic straight away.
Blood sugar
The amount of glucose in one litre of blood is called your blood sugar level. In most people, the body controls this level effectively at around 1 gram of glucose per litre. However, in people with diabetes, the body does not control blood sugar levels properly. Levels that are too high or too low cause serious health problems.
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