Digestive System

Question 1

What are the parts of the alimentary canal?

Answer 1

• Oesophagus
• Stomach
• Duodenum
• Small intestine
• Large intestine
• Rectum
• Anus

Question 2

What organs are needed for digestion?

Answer 2

• Salivary glands
• Liver
• Gall bladder
• Pancreas

Question 3

What are carbohydrate’s basic building block?

Answer 3

Sugar

Question 4

What are protein’s basic building block?

Answer 4

Amino acids

Question 5

What are lipids (fats) basic building block?

Answer 5

Fatty acids and glycerol

Question 6

What is nucleic acid’s basic building block?

Answer 6

Nucleotides

Question 7

What type of digestion occurs in the mouth?

Answer 7

Mechanical digestion - teeth tear food
Chemical digestion - enzymes

Question 8

What digestive enzyme is in the mouth and what does it do?

Answer 8

Amylase which breaks down carbohydrates.

Question 9

What are the oesophagus muscles?

Answer 9

A double layer of circular and longitudinal muscle.

Question 10

What is peristalsis?

Answer 10

When rhythmic contractions push the bolus down the tubes.

Question 11

What are the stomach muscle’s names?

Answer 11

Longitudinal, circular and oblique.

Question 12

Stomach digestion?

Answer 12

Mechanical digestion - rhythmic contractions.
Chemical digestion - enzymes.
Absorption - alcohol and drugs into bloodstream

Question 13

What are the enzymes in the stomach?

Answer 13

Gastric protease - Pepsin

Question 14

Chemical digestion in small intestines?

Answer 14

Intestinal juices - secreted by glands in the lining of the small intestine.
Pancreatic juices - secreted by the pancreas
Bile - made by the liver

Question 15

What do pancreatic juices do?

Answer 15

Neutralise the acid that comes from the stomach?

Question 16

What enzymes are in pancreatic juices and what do they do?

Answer 16

Pancreatic amylase (carbohydrates)
Pancreatic protease - Trypsin (proteins)
Pancreatic lipase (fatty acids and glycerol)
Ribonuclease and Deoxyribonuclease (RNA and DNA)

Question 17

Bile salts?

Answer 17

A form of mechanical digestion. Coats the outside of the fat molecule (emulsifies) so that it doesn’t contact the water.

Question 18

Where is bile stored?

Answer 18

Gall bladder

Question 19

Amylases break down what?

Answer 19

Disaccharides to simple sugars.

Question 20

Peptidases break down what?

Answer 20

Peptides to amino acids.

Question 21

Lipases break down what?

Answer 21

Lipids to fatty acids and glycerol.

Question 22

What is absorbed through the walls of the SI and carried by the hepatic portal vein to the liver?

Answer 22

Simple sugars, amino acids, water and water-soluble vitamins; absorbed in to blood capillaries.

Question 23

What is the inner lining of SI and what does it do?

Answer 23

The inner lining is called mucosa and is folded with villi that extend from it.

Question 24

Large surface area of SI =

Answer 24

• Efficient and maximum absorption

Question 25

Structure of villi?

Answer 25

1mm long and covered by a single layer of cells.

Question 26

How do the villi make contact with the food?

Answer 26

Muscular movement (peristalsis) continually moves the villi.

Question 27

What is inside each villi?

Answer 27

Lymph capillary called a lacteal.

Question 28

What is absorbed in the lacteal?

Answer 28

Fats and fat solubles.

Question 29

Is water absorbed in the large intestine?

Answer 29

Yes, most of it.

Question 30

Bacteria's role in the SI?

Answer 30

breaks down remaining organic compounds (last thing to occur). Nutrients, vitamins and minerals are absorbed through cell wall in to blood.

Question 31

What do faeces contain?

Answer 31

Water, undigested food material (cellulose), bacteria, bile pigments (colour) and any cells that have broken away from the internal lining of the alimentary canal.