Digestive System

Question 1

What is a heterotroph?

Answer 1

An organism that cannot make its own food.

Question 2

What is the function of the alimentary canal?

Answer 2

Ingest, mechanically/chemically digest, absorb nutrients, and egest waste

Question 3

What organs make up the human digestive system?

Answer 3

Alimentary canal, salivary glands, liver, pancreas

Question 4

What are the three parts of the small intestine?

Answer 4

Duodenum, jejunum, ileum

Question 5

What are the four parts of the large intestine?

Answer 5

Caecum, colon, rectum, anal canal

Question 6

What is the function of the mouth in digestion?

Answer 6

Chewing (mechanical digestion) and mixing with saliva

Question 7

What is saliva composed of?

Answer 7

Water, mineral salts, salivary amylase, mucin, lysozyme

Question 8

What is peristalsis?

Answer 8

Muscle contractions that move food through the alimentary canal

Question 9

What are examples of the gastric pit secretions?

Answer 9

HCl, pepsinogen, GIF, mucus.

Question 10

What does pepsin do?

Answer 10

Breaks proteins into polypeptides in acidic conditions

Question 11

What are the three parts of the small intestine?

Answer 11

Duodenum (digestion), jejunum & ileum (absorption)

Question 12

What is bile’s function?

Answer 12

Emulsifies fats, neutralizes acid, aids peristalsis

Question 13

What enzymes does pancreatic juice contain?

Answer 13

Amylase, lipase, trypsin, chymotrypsin, nucleases

Question 14

How are glucose and galactose absorbed?

Answer 14

Actively transported into blood capillaries

Question 15

What are micelles?

Answer 15

Fatty acids + bile salts, aiding lipid absorption

Question 16

What is the main function of the large intestine?

Answer 16

Absorb water, form vitamins, and expel waste

Question 17

What protects the stomach from self-digestion?

Answer 17

Mucus and secretion of inactive pepsinogen

Question 18

How is bile secretion controlled?

Answer 18

By the hormone Secretin

Question 19

What are chylomicrons?

Answer 19

Fat-protein complexes absorbed into the lymph

Question 20

What are the roles of villi in the small intestine?

Answer 20

Increase surface area for nutrient absorption

Question 21

What triggers gastric juice secretion?

Answer 21

Nervous system (smell/sight) and hormone gastrin

Question 22

What are the key functions of the stomach?

Answer 22

Mix food, digest proteins, absorb alcohol and salts, secrete gastric intrinsic factor (GIF)

Question 23

What is chyme?

Answer 23

Semi-liquid material produced in the stomach and passed into the duodenum

Question 24

What is the role of HCl in the stomach?

Answer 24

Provides optimum pH, denatures proteins, starts hydrolysis of food, and kills bacteria

Question 25

What are the phases of gastric secretion?

Answer 25

Nervous (smell/taste), gastric (hormone gastrin), intestinal (duodenum hormones)

Question 26

What do Brunner's glands secrete?

Answer 26

Alkaline mucus to neutralize acidic chyme and protect the duodenum

Question 27

What activates trypsinogen into trypsin?

Answer 27

The enzyme enterokinase in the small intestine

Question 28

What is the role of secretin?

Answer 28

Stimulates pancreatic juice secretion

Question 29

What does cholecystokinin (CCK) do?

Answer 29

Stimulates the gallbladder to release bile

Question 30

What are the main components of bile?

Answer 30

Water, bile salts, bile pigments, mucus, cholesterol

Question 31

How does the small intestine protect itself from digestive enzymes?

Answer 31

By secreting mucus and alkaline solutions

Question 32

What are mesenteries?

Answer 32

Layers that support the intestines within the abdominal cavity

Question 33

What is the function of the crypts of Lieberkühn?

Answer 33

Secrete intestinal juice containing enzymes and mucus

Question 34

What enzymes are found in pancreatic juice?

Answer 34

Trypsin, chymotrypsin, amylase, lipase, and nucleases

Question 35

What is the purpose of emulsification by bile?

Answer 35

Break down fat into smaller droplets for easier digestion

Question 36

How are proteins absorbed in the small intestine?

Answer 36

As amino acids via active transport into epithelial cells

Question 37

What happens to undigested food in the large intestine?

Answer 37

It is compacted into faeces and expelled during egestion

Question 38

What is the role of stratified epithelium in the alimentary canal?

Answer 38

Protects the lining from abrasion and digestive enzymes

Question 39

What stimulates gastric emptying?

Answer 39

Nervous signals and gastrin in response to chyme and stomach stretching

Question 40

How are lipids transported after absorption?

Answer 40

As chylomicrons via the lymphatic system into the bloodstream

Question 41

What is the role of the liver in digestion?

Answer 41

Produces bile, detoxifies substances, and stores nutrients

Question 42

What are the main nutrients absorbed in the small intestine?

Answer 42

Amino acids, sugars, fatty acids, vitamins, and minerals

Question 43

How does the ileum connect to the large intestine?

Answer 43

Via the caecum