Gastrointestinal system

Question 1

Layers of the alimentary canal

Answer 1

Mucosa, submucosa, muscularis and serosa

Question 2

Sublayers of the mucosa

Answer 2

Epithelium, lamina propria and muscularis mucosa

Question 3

Epithelium of the stomach and intestines

Answer 3

Simple columnar epithelium

Question 4

Epithelium of the GI tract except the stomach and intestines

Answer 4

Non-keratinized squamous epithelium

Question 5

In which layer to goblet and enteroendocrine cells exist?

Answer 5

The epithelium of the mucosa

Question 6

Lamina propria

Answer 6

Consists of loose connective tissue, blood and lymph vessels. Also contains MALT

Question 7

MALT

Answer 7

Mucosal Associated Lymphoid Tissue, Peyer’s patches in the intestines

Question 8

Muscularis mucosa

Answer 8

Thin smooth muscle layer in a constant state of tension. Pulls the mucosa of the stomach and small intestine into undulating folds to increase surface area.

Question 9

Submucosa

Answer 9

Contains dense connective tissue, blood and lymph vessels, submucosal glands, submucosal plexus

Question 10

Muscularis

Answer 10

Smooth muscle layer. Contraction produces peristalsis, mixing and mechanical digestion

Question 11

Proximal and distal regions of the muscularis

Answer 11

Skeletal muscle under volontary control

Question 12

Myenteric plexus

Answer 12

Nerve plexus which lies in the muscularis layer and is responsible for motility.

Question 13

Segmentation

Answer 13

Chyme is separated, then pushes back together.

Question 14

Serosa

Answer 14

Layer which surrounds the muscularis. Present only in the abdominal cavity region. Consists of visceral peritoneum overlaying loose connective tissue

Question 15

Peritoneum

Answer 15

Broad serous membranous sac made of squamous epithelial tissue. Holds the digestive organs in place.

Question 16

Parietal peritoneum

Answer 16

Lines the abdominal wall

Question 17

Visceral peritoneum

Answer 17

Envelops the abdominal organs

Question 18

Peritoneal structures

Answer 18

Greater and lesser omentum, mesentery and mesocolon

Question 19

Greater omentum

Answer 19

Apron structure superior to the small intestine and transverse colon. Fat can be deposited here.

Question 20

Lesser omentum

Answer 20

Suspends the stomach from the inferior border of the liver

Question 21

Mesentery

Answer 21

Vertical band of tissue which anchors the small intestine escept the duodenum

Question 22

Mesocolon

Answer 22

Attaches the transverse and sigmoid colon to the posterior abdominal wall

Question 23

Regulatory mechanisms for digestion

Answer 23

Neural and endocrine

Question 24

Main hormones of the GI system

Answer 24

Gastrin, secretin, cholecystokinin, gastric inhibitory peptide

Question 25

Gastrin

Answer 25

Digestive hormone of the stomach. Secreted in response to food. Stimulates secretion of gastric acid by parietal cells.

Question 26

Secretin

Answer 26

Produced by the duodenum. Stimulates the release of bicarbonate from the pancreas.

Question 27

Cholecystokinin

Answer 27

Secreted by the small intestine. Stimulates the secretion of pancreatic enzymes and bile.

Question 28

Gastric inhibitory peptide

Answer 28

Inhibits gastric secretion, slows gastric emptying and motility.

Question 29

Receptors on the tongue

Answer 29

Fungiform papillae (taste buds) and filiform papillae (touch receptors)

Question 30

Functions of saliva

Answer 30

Amylase, chemical buffers, lubrication and antimicrobial properties

Question 31

How does the esophagus enter the abdomen?

Answer 31

Via the esophageal hiatus

Question 32

Salivary glands

Answer 32

Submandibular, sublingual and parotid.

Question 33

Largest salivary gland

Answer 33

Parotid

Question 34

Layers of the tooth

Answer 34

Enamel, dentin, pulp

Question 35

Phases of deglutition

Answer 35

Volontary, pharyngeal, esophageal

Question 36

Muscularis layer of the esophagus

Answer 36

Is skeletal in the top third, mixed skeletal and smooth in the middle third and smooth in the bottom third.

Question 37

Major regions of the stomach

Answer 37

Caria, fundus, body, pylorus

Question 38

Muscular layers of the stomach

Answer 38

Consists of 3 layers. Inner circular, middle longitudinal and external oblique layers.

Question 39

Special cells of the stomach

Answer 39

Mucus, parietal, chief and enteroendocrine

Question 40

Mucus cells of the stomach

Answer 40

Secrete a protective coat of alkaline mucous.

Question 41

Parietal cells

Answer 41

Produce HCl and intrinsic factor

Question 42

Intrinsic factor

Answer 42

A glycoprotein secreted by parietal cells which protects vitamin B12 through the stomach

Question 43

Chief cells

Answer 43

Secrete pepsinogen and gastric lipase.

Question 44

Enteroendocrine cells of the stomach

Answer 44

Secrete various stomach hormones. Includes gastrin from G cells.

Question 45

Phases of gastric secretion

Answer 45

Cephalic, gastric and intestinal

Question 46

Gastric phase of gastric secretion

Answer 46

Has neural and hormonal components. Causes increase in gastric juice, gastrin and HCl

Question 47

Intestinal phase of gastric secretion

Answer 47

Has excitatory and inhibitory elements. Increases gastric juice secretion, but closes pyloric sphincter

Question 48

Functions of the stomach

Answer 48

Antimicrobial, mechanical and chemical digestion.

Question 49

How much chyme enters the small intestine at one?

Answer 49

3mL

Question 50

Substances absorbed by the stomach

Answer 50

Some non-polar substances such as alcohol and some drugs.