Body Systems - 3.1 Digestion

Question 1

What are humans made up of?

Answer 1

Millions of tiny building blocks called cells.

Question 2

Where is most of the body’s work carried out?

Answer 2

In the cells.

Question 3

What are the five systems of your body and what do they do?

Answer 3

Respiratory - takes in oxygen

Digestive - makes food available in a form the body can use

Circulatory - carries food and oxygen to where it is needed

Excretory - gets rid of wastes

Skeletal - supports the body and enables it to move

Question 4

What is digestion?

Answer 4

The process of breaking down food into a useable form and making nutrients available.

Question 5

What does the digestive system consist of?

Answer 5

• Digestive tract - pathway that food takes through a series of organs.
• Organs off to the side of the digestive tract that produce chemicals that help with digestion.

Question 6

What are the two types of digestion?

Answer 6

• Mechanical digestion
• Chemical digestion

Question 7

What is mechanical digestion?

Answer 7

When food is broken down into smaller pieces.

Question 8

What is chemical digestion?

Answer 8

When large, complex substances in the food are broken down into simpler chemicals.

Question 9

Where does digestion start?

Answer 9

With the teeth.

Question 10

What are the four types of teeth?

Answer 10

• Incisors
• Molars
• Pre-molars
• Canines

Question 11

What do the incisors, molars and pre-molars do?

Answer 11

Incisors bite off pieces small enough to chew, which are pushed back to where the molars and pre-molars grind food into smaller pieces as you chew.

Question 12

What does saliva do?

Answer 12

Changes any starch to glucose, also moistens the food making it easier to swallow.

Question 13

What is ‘peristalsis’?

Answer 13

When the muscles of the oesophagus push down food by contracting behind the food.

Question 14

What does the epiglottis do?

Answer 14

Closes the end of your windpipe so the food goes into the stomach, not the windpipe.

Question 15

What does the stomach’s sphincter do?

Answer 15

Separates the stomach from the oesophagus, which makes an opening so food passes through before it closes so no food flows back up.

Question 16

What role does the stomach play in digestion?

Answer 16

Changes the food by contracting and relaxing the muscular walls, churning it up, and the chemicals inside also breaks down the food.

Question 17

How does the stomach digest the food mechanically?

Answer 17

Mixing it with gastric juice, which is produced by special cells in the stomach.

Question 18

What does gastric juice contain?

Answer 18

Hydrochloric acid - strong acid that kills bacteria

Mucus - layer on lining of stomach, prevents stomach from consuming itself LOL what the hay that is so silly?!?!

Digestive juices - contains chemicals that start digestion of protein.

Question 19

What is the small intestine?

Answer 19

It is a long, narrow tube. It is the largest part of your digestive tract.

Question 20

What is the first part of the small intestine and how does it help with digestion?

Answer 20

The duodenum, it has two tubes from the pancreas and liver that carry chemicals that are important for digestion.

Question 21

What does the pancreas do? (cfp)

Answer 21

The pancreas is not part of the digestive tract, it is an organ that produces pancreatic juice which contains chemicals that help digest carbohydrates, fat and protein.

Question 22

What is the liver’s purpose?

Answer 22

The liver produces ‘bile’ which breaks down large pieces of fat so they can be digested more easily.

Question 23

What does the duodenum do?

Answer 23

The stomach’s muscular walls squeeze and churn food, mixing it with digestive chemicals to break it down into forms the body can absorb.

Question 24

What form is the food in when it passes into the lower part of the small intestine (ileum)?

Answer 24

Tiny particles that can be absorbed by the body.

Question 25

What are ‘villi’?

Answer 25

Microscopic ‘fingers’ that are on the inner lining of the ileum, which increase the surface area of the intestine wall, so the nutrients from the food can pass.

Question 26

What are capillaries?

Answer 26

Tiny blood vessels within the villi, which insure the nutrients only travel a small distance from the digestive system into the blood system.

Question 27

What are the nutrients that pass from the small intestine?

Answer 27

• fatty acids and glyrecol produced from digestion of fats
• amino acids from digestion of protein
• glucose (main source of energy for the body) from the digestion of carbohydrates

Question 28

What is the large intestine and what does it do?

Answer 28

It is the last section of the digestive tract, it re-absorbs water into the body from what food is left, along with any remaining nutrients.

Question 29

What does the waste produced in the large intestine form?

Answer 29

Lumps of faeces (known as stools), which later come out through the anus (a sphincter muscle). About ⅓ of faeces is made of bacteria.

Question 30

What does vomiting do?

Answer 30

It is a quick way of getting rid of unwanted bacteria in the digestive tract. It happens when stress or infection causes the muscular wall of the stomach to contract.

Question 31

What happens inside the body when you vomit?

Answer 31

The sphincters at the top and bottom of the stomach open, and the contents come up the oesophagus and out of the mouth.

Question 32

What does diarrhoea do?

Answer 32

It is another quick way of getting rid of bad bacteria and viruses.

Question 33

Why do you become at risk of dehydration when you have diarrhoea?

Answer 33

The lining of the small intestine becomes inflamed and stops water from being absorbed by the now loose faeces.

Question 34

What is heartburn?

Answer 34

A burning sensation that rises up the oesophagus from the stomach, which causes pressure on the stomach, leading to contents being pushed up, creating a burning feeling.

Question 35

Why does heartburn happen?

Answer 35

The oesophagus does not have a lining of mucus, so the burning is the acids attacking the lining of the oesophagus.

Question 36

What is the appendix?

Answer 36

The appendix is a blind-ended tube connected to the large intestine.

Question 37

How does appendicitis happen?

Answer 37

If the opening of the appendix is blocked, the appendix fills with mucus. It then becomes inflamed and swollen, causing pain.