Chapter 3: Nutrition | Reading and Writing Practice

Read the passage below and then answer the following questions.

Your body breaks down carbohydrates into the sugar known as glucose, which is your brain and central nervous system’s preferred source of energy. Glucose powers your brain, enabling you to concentrate and pay attention. Have you ever skipped breakfast and then had trouble concentrating in one of your early morning classes? This difficulty is caused by your body running out of glucose.

When your body needs more energy, it can use glucose immediately. This is why having a candy bar or soft drink, both loaded with sugar, can give you a quick “pick-me-up.” The sucrose in these snacks is quickly and easily broken down into glucose and fructose.

When glucose is stored in the muscles and liver for later use, it is known as glycogen. After enough glycogen has been stored, any extra glucose is converted by the liver into fat, which is stored in the fat tissue. The body uses glycogen from the muscles and liver, or the stored fat, when it needs energy between meals or to fuel activity.


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