Science - Chapter 3 - Lesson 3 - Digestive and Urinary System

Question 1

What is the job of the Digestive System?

Answer 1

Food has to be changed before your cells can use it. Your body first has to digest (break down) food into very small materials. Then it can enter the blood to get to your cells. This process is call digestion and it is very hard and it takes many organs working together.

Question 2

What are the parts of the Digestive System?

Answer 2

1. mouth
2. esophagus
3. stomach
4. liver
5. pancreas
6. small intestines
7. large intestine

Question 3

What is the first step of digestion?

Answer 3

Chewing! chewing makes food small and it makes the job of the rest of the digestive system easier.

Question 4

What does the esophagus do?

Answer 4

The esophagus is a tube that carries food to the stomach. The food doesn’t go down by gravity. The esophagus pushes food to the stomach by squeezing it’s rings of muscles in a pattern. As the lump of food passes each ring of muscle, the muscles behind the food contracts and this pushes the food through the esophagus to the stomach in abut two or three seconds.

Question 5

Where is the stomach located?

Answer 5

At the bottom of the esophagus, under your lower left ribs.

Question 6

What is the stomach?

Answer 6

It’s a tight round muscle. The stomach walls can stretch to store all of the food from a meal.

Question 7

How does the stomach work?

Answer 7

When you swallow, this muscle relaxes and opens to let food into your stomach. Then the muscle closes to keep food from moving back into your esophagus. It produces fluids that help to digest foods. As the muscles in the stomach’s walls squeeze, these fluids mix with the food. After it becomes a soupy paste, it is ready to leave your stomach.

Question 8

What happens after the food leaves the stomach?

Answer 8

The stomach pushes the soupy paste into a narrow, winding tube called the small intestine. Its muscles squeeze the food in one direction and receive chemicals from the liver and pancreas to digest the food.

Question 9

What are the organs that send chemicals to your small intestine to help digest food?

Answer 9

liver and pancreas.

Question 10

What happens once digestion is finished?

Answer 10

The particles of digested food can move into blood vessels that are in the walls of your intestine.

Question 11

What is villi?

Answer 11

Villi are tiny finger shaped structures that are found all over the inside walls of the small intestine. They give the small intestine more surface area to absorb food.

Question 12

What happens at the end of the small intestine?

Answer 12

Food that cannot be digested remains there. This moves into a wider tube called the large intestine (also known as the colon).

Question 13

What happens in the large intestine?

Answer 13

Helpful bacteria live in the large intestine. Some bacteria make vitamins that your body uses. It also helps keep out other bacteria that cause disease. The large intestine takes out water and salt from the waste making it more solid. Finally, muscles squeeze to push the waste out of the body.

Question 14

What is the Urinary System?

Answer 14

The urinary system is the way your body has to get rid of waste. If you don’t get rid of it you won’t live for long.

Question 15

What are kidneys?

Answer 15

The kidneys are a pair of organs that remove waste from your blood.

Question 16

How do kidneys look and where are they located?

Answer 16

The kidneys look like kidney beans and have dark red color. They are located on either side of your backbone, just under your lower ribs.

Question 17

How do kidneys work?

Answer 17

When wastes are filtered out of the blood, many of the materials also leave the blood. These other materials include water, salt, calcium, nutrients and other chemicals your body needs. The kidney has to put the right amount of these materials back into the blood to keep the body healthy. They help keep the amount of these materials of getting too high or too low.

Question 18

What is urine?

Answer 18

It’s a mix of water and waste produced by the kidneys.

Question 19

How does urine get out of the body?

Answer 19

A tube carries urine away from the kidneys into your urinary bladder. The bladder stores urine. At the bottom of the bladder is a tight round muscle that keeps the urine inside until it is removed from the body.

Question 20

What are other ways the body gets rid of waste?

Answer 20

Carbon dioxide is removed by the lungs.

Cells’ waste are removed by sweat glands.