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Our digestive and excretory systems.

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Why do we eat and drink?

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Why do we go to the toilet?

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Read and think.

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One, read and answer.

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What happens to food in each parts of the digestive system?

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B, what is the most important part of the excretory system?

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Our digestive system helps us to get the nutrients we need from food.

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1. The mouth has teeth that break the food into small pieces and a tongue that mixes the food with saliva so it's easy to swallow.

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2. The esophagus is a long tube. Food goes down here to the stomach.

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3. The stomach is like a bag. The food stays here for about three hours.

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Gastric juices break down the food even more and turn it into a thick liquid.

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The thick liquid leaves the stomach and goes into the small intestine.

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Four, the small intestine is a very long, thin tube.

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There are lots of blood vessels around the tube.

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The thick liquid from the stomach goes through here and the nutrients pass into the blood.

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Five, the large intestine is a wide tube.

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It connects to the anus. What our body doesn't need goes along here and out through the anus

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when we go to the toilet. Our excretory system helps our bodies to get rid of excess water and

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waste products. One, the blood goes through the kidneys. The kidneys remove excess water and waste

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products from the blood and turns them into urine. Two, the ureters are long tubes where the urine

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goes down to the bladder. Three, the bladder is like a bag. It collects the urine. When it is

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full, it sends messages to our brain. It is time to go to the toilet. Four, the urethra is a short

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tube. Urine goes down here and leaves our body when we go to the toilet.