B3 - Organisation and The Digestive System

Question 1

What is a tissue?

Answer 1

• A group of cells with similar structure and function.

Question 2

What is an organ?

Answer 2

• Collections of tissues performing specific functions.

Question 3

What is an organ system?

Answer 3

• Organs are organised to make them, they work together to form organisms.

Question 4

What does a liver do?

Answer 4

• Produces bile.

Question 5

What does the mouth do?

Answer 5

• Where food enters and digestion begins.

Question 6

What is the function of the salivary glands?

Answer 6

• Produce saliva containing amylase.

Question 7

What is the function of the oesophagus?

Answer 7

• Muscular tube which moves ingested food to the stomach.

Question 8

What is the function of the stomach?

Answer 8

• Muscular organ where digestion continues.

Question 9

What is the function of the gall bladder?

Answer 9

• Stores bile before releasing it to the duodenum.

Question 10

What is the function of the small intestine?

Answer 10

• Food is mixed with digestive enzymes and bile.

- Where digested food is absorbed into the blood and lymph.

Question 11

What is the function of the large intestine?

Answer 11

• Where water is reabsorbed.

Question 12

What is the function of the rectum?

Answer 12

• Where faeces are stored.

Question 13

What is the function of the anus?

Answer 13

• Where faeces leave the body.

Question 14

What are simple sugars?

Answer 14

• Type of carbohydrate that only contain one or two sugar units.

Question 15

What are complex carbohydrates?

Answer 15

• Type of carbohydrate that contain long chains of simple sugar units bonded together.

Question 16

What are fatty acids?

Answer 16

• Lipids that consist of 3 molecules to make up glycerol.

Question 17

What are protein molecules?

Answer 17

• Type of protein made up of long chains of amino acids.

Question 18

What is a catalyst?

Answer 18

• Increase the rate of chemical reactions without chemically changing themselves.

Question 19

What is an enzyme?

Answer 19

• Biological catalysts and catalyse specific reactions in living organisms due to the shape of their active site.

Question 20

What type of food is an enzyme?

Answer 20

• Protein.

- Amino acid chains are folded to from the active site which matches the shape of a specific substrate molecule.

Question 21

What happens to the substrate and the active site after the amino acids form the active site?

Answer 21

• Substrate binds to the active site and the reaction is catalysed by the enzyme.

Question 22

What is a metabolism?

Answer 22

• Sum of all the reactions in a cell or the body.

Question 23

How is enzyme activity affected?

Answer 23

• Temperature and pH.

Question 24

How do high temperatures denature the enzyme?

Answer 24

• They change the shape of the active site.

Question 25

How does a pH affect the shape of an active site?

Answer 25

- Make it work very efficiently or stop it work.

Question 26

What happens during the process of digestion?

Answer 26

- Breakdown of large insoluble molecules into soluble substances that can be absorbed into the blood across the small intestine.

Question 27

How are digestion enzymes produced?

Answer 27

- Specialised cells in the glands and in the lining of the digestive system.

Question 28

What do carbohydrases catalyse?

Answer 28

- Breakdown of carbohydrates to simple sugars. | - Amylase.

Question 29

What do proteases catalyse?

Answer 29

- Breakdown of proteins to amino acids.

Question 30

What do lipases catalyse?

Answer 30

- Breakdown of lipids to fatty acids and glycerol.

Question 31

How does Hydrochloric acid affect the stomach?

Answer 31

- Gives the stomach a low pH suitable for the protease secreted there to work efficiently.

Question 32

How does alkaline bile affect organs like the small intestine and the pancreas?

Answer 32

- Neutralises the acid and gives a high pH for the enzymes to work well.

Question 33

What does bile do and what is it?

Answer 33

- Not an enzyme as it doesn't break down fat molecules. - Emulsifies the fat into tiny droplets which increases the surface area for lipase to increase the rate of digestion. - Produced by liver stored in the gall bladder and released through the bile duct.