Gastrointestinal

Question 1

Epithelium:
Simple \_\_ layer(s)
Stratified \_\_ layer(s)
Pseudostratified \_\_ layer(s)
Squamous: \_\_\_ cells
Columnar: \_\_\_ cells

Answer 1

Simple 1 layer
Stratified >1 layer
Pseudostratified 1 layer that pretends to be 2
Squamous: flat cells
Columnar: column-like cells

Question 2

State the main 3 salivary gland types.

Answer 2

Parotid, submandibular & sublingual glands.

Question 3

What are the functions of saliva?

Answer 3

Lubricant (mucin content), digestion (α-amylase), protection of oral mucosa (lubricates, rinses, alkaline pH), antibacterial, thirst stimulation, speech, absorption in mouth.

Question 4

State the main 3 muscles of mastication and their functions.

Answer 4

Temporalis (elevates jaw), masseter (elevates & protrudes lower jaw) & pterygoids (lateral movement of lower jaw)

Question 5

State the 4 basic layers of the digestive tract.

Answer 5

mucosa, submucosa, muscularis externa, serosa.

Question 6

State the 3 layers of mucosa and briefly describe their structure and function.

Answer 6

Epithelium (selective barrier; conatins goblet cells & endocrine cells), lamina propria (loose connective tissue; rich blood supply, immunological barrier), muscularis mucosa (thin layer of smooth muscle cells)

Question 7

Describe the structure & function of submucosa.

Answer 7

Dense connective tissue: contains the submucosal plexus - part of the enteric nervous system.

Question 8

Describe the function of muscularis externa.

Answer 8

PERISTALSIS (motility)

Question 9

Describe the function of serosa.

Answer 9

Part of the peritoneum - covers & anchors abdominal organs to body wall.

Question 10

State the 4 main regions of the stomach.

State the 2 sphincters.

Answer 10

oesophageal sphincter, FUNDUS, BODY, ANTRUM, PYLORUS, pyloric sphincter.

Question 11

State the 3 layers of the Muscularis (stomach)

Answer 11

Longitudinal, Circular, Oblique muscle layer.

Question 12

What do the fundus & body secrete

Answer 12

Acid from parietal cells, and pepsin precursor & pepsinogen from peptic (chief) cells.

Question 13

3 endocrine secretions from the antral region include:

Answer 13

gastrin, histamine & somatostatin.

Question 14

What is the peritoneum?

Answer 14

A layer of connective tissue which covers abdomen organs.

Question 15

State the 3 regions of the small intestine.

Answer 15

Duodenum, jejunum, ileum.

Question 16

What are the 4 types of specialised cell present in villi?

Answer 16

Absorptive, goblet, granular & APUD cells.

Question 17

State some functions of the liver.

Answer 17

Glucose storage, protein lipoprotein & cholesterol synthesis, bile salts - digestion, storage of fat soluble vits (A,D,E,K), toxin & drug metabolism/excretion.

Question 18

State the 2 components of pancreatic juice & their function.

Answer 18

Alkaline secretions: high bicarbonate content - neutralises acidic gastric contents.
Pre-enzyme secretions - activated in gut.

Question 19

What is the main zymogen (prepeptidase)? What is it activated to?

Answer 19

Trypsinogen -> trypsin via enteropeptidase.

Question 20

Where are the liver & gall bladder located?

Answer 20

Right upper quadrant of abdomen, directly beneath diaphragm.

Question 21

Describe the epithelium structure in the large intestine.

Answer 21

Simple columnar & contains crypts. Many goblet & absorptive cells present. Few APUD cells.

Question 22

What are the main 3 regions of the large intestine>

Answer 22

Caecum, colon & rectum.

Colon -> ascending & descending regions.

Question 23

State the main function of the large intestine

Answer 23

Absorption of water & ions. Some nutrients absorbed, mainly in the colon.