GI Tract

Question 1

What is the function of the digestive system?

Answer 1

The digestive system digests food so that the body can absorb nutrients and excrete waste.

Question 2

Identify the components of the GI Tract

Answer 2

Mouth, salivary glands, pancreas, small intestine, large intestine, stomach and anus

Question 3

What are the 3 main functions of the tongue?

Answer 3

Allows food to be properly mixed with saliva
Moves food from mouth to oesophagus
Speech

Question 4

What is the collective name given to the numerous small projections on the surface of the tongue used for grooming?

Answer 4

Papillae

Question 5

What is the function of saliva?

Answer 5

Moisten the mouth
Lubrication for food to move
Soften food
Production pf amylase to break down carbohydrates

Question 6

Describe the event of swallowing.

Answer 6

Stage 1 - Buccal Phase = tongue pushes food to back of mouth

Stage 2 - Pharyngeneal phase = involuntary signals block food from going down to lungs

Stage 3 - Oesophagal phase = food moves down oesophagus by muscle contractions and relaxing.

Question 7

Identify the different regions of the stomach.

Answer 7

Cardia - end of oesophagus
Fundus - top
Body - main region
Pylorus - start of intestine

Question 8

State the term used to describe the muscles contractions which move food down the oesophagus.

Answer 8

Peristalsis

Question 9

What are rugrae

Answer 9

folds on the stomach lining which flatten when the stomach is full

Question 10

What is meant by the term gastric?

Answer 10

Anything in relation to the stomach

Question 11

Describe the function of mucus.

Answer 11

Protection of stomach lining

Question 12

Describe the function of hydrochloric acid.

Answer 12

Keeps pH low to allow efficient function of pepsin

Question 13

Describe the function of pepsinogen.

Answer 13

Produces pepsin

Question 14

Describe the function of gastrin.

Answer 14

Stimulation of hydrochloric acid production.

Question 15

Describe the function of lipase.

Answer 15

Breakdown of fat.

Question 16

What is chyme?

Answer 16

The mixture of food, saliva and gastric secretions that leave the stomach

Question 17

What is the function of goblet cells?

Answer 17

Mucus production.

Question 18

Define vomitting.

Answer 18

A reflex act of expulsion of stomach contents through the oesophagus and mouth.

Question 19

Identify the 3 regions of the small intestine.

Answer 19

Duodenum
Jejunum
Ileum

Question 20

Describe what the duodenum of the small intestine is for.

Answer 20

Joins small intestine with the stomach.

Question 21

Describe what the jejunum of the small intestine is for.

Answer 21

Absorbs nutrients from food stuffs that travel through the small intestine.

Question 22

Describe what the ileum of the small intestine is for.

Answer 22

Connects small and large intestine.

Question 23

List the 3 secretions of the small intestine.

Answer 23

Pancreatic juice
Bile
Intestinal juice

Question 24

Identify the role the pancreas plays in the digestive system.

Answer 24

Produces pancreatic juice which neutralizes stomach acid

Question 25

Identify the role of the liver and the gallbladder.

Answer 25

The liver produces bile and the gallbladder stores the bile.

Question 26

Define the oesophagus.

Answer 26

Thin walled muscle which passes through diaphragm to reach stomach Food travels from mouth to stomach through oesophagus

Question 27

Define the role of the stomach.

Answer 27

Storage organ which breaks down food.

Question 28

Describe the role of the large intestine

Answer 28

Digestion, defaecation, reflux control.

Question 29

Identify the three salivary glands found in humans and state their location.

Answer 29

Parotid - posterior to pharynx Submandibular - inferior to tongue Subligual - inferior to submandibular gland.

Question 30

Describe the 2 main constituents of bile.

Answer 30

Bile salts - involved in fat breakdown Bile Pigments (bilirubin, biliverdin) - waste products from liver

Question 31

List the functions of the liver.

Answer 31

``` Bile production Synthesis of proteins Breakdown of ammonia to urea Fat metabolism Storage of fat soluble vitamins Storage of iron ```

Question 32

State the term used to describe the projections found along the inner lining of the small intestine.

Answer 32

Villi

Question 33

What is the function of villi?

Answer 33

Absorption of small intestine contents

Question 34

Describe the structure of a villus

Answer 34

Outer layer - absorptive cells Inner layer - lymph capillary (lacteal) surrounded by blood capillaries

Question 35

Describe the structure of the large intestine.

Answer 35

Caecum - first part of large intestine after small intestine Ascending colon - up along small intestine Transverse colon - over small intestine Descending colon - down side of small intestine Sigmoid colon - connects descending colon to rectum Rectum - storage for fecal matter

Question 36

Define chyle

Answer 36

Milky fluid containing digested fats which are absorbed by lacteals

Question 37

What are lacteals?

Answer 37

Lymphatic capillaries found in villi

Question 38

List the essential food stuffs humans require.

Answer 38

``` Protein Carbohydrates Fat Water Vitamins Mineral salts Water ```