Grand Tour of The Alimentary Systems

Question 1

What are the functions of the digestive system?

Answer 1

• Digestion
• Secretion
• Absorption
• Motility

Question 2

What are the three salivary glands?

Answer 2

Parotid

Sublingual

Submandibular

Question 3

What happens in the stomach?

Answer 3

Digestion of proteins, foodstuffs reduced to liquid form, sterilisation

Question 4

What are the digestive enzymes in the pancreas used for?

Answer 4

Digestion of fats, proteins and carbohydrates

Question 5

What is the function of the liver?

Answer 5

Bile salts for digestion/absorption of fats in small intestine

Question 6

What is the function of the gallbladder?

Answer 6

Stores and concentrates bile

Question 7

What is the function of the small intestine?

Answer 7

Final stages of chemical digestion and nutrient absorption

Question 8

What is the function of the large intestine?

Answer 8

Water absorption, bacterial fermentation and formation of faeces

Question 9

What are the different layers of the alimentary canal?

Answer 9

Mucosa

Submucosa

Muscularis externa

Serosa/adventita

Question 10

What is the mucosa composed of?

Answer 10

Epithelium

Lamina propria

Muscularis mucosae (no significant function)

Question 11

What is the function of the muscularis externa?

Answer 11

Where all the motility comes from

Question 12

When is the serosa called the adventita?

Answer 12

The shiny connective tissue sheath is known as the serosa below the diaphrafm, but above it is known as the adventitia

Question 13

What is the inner layer of the muscularis externa?

Answer 13

Inner layer is the circular muscle layer

Outside that is the longitudinal muscle layer

Question 14

Where in the digestive tract can you find stratified squamous epithelium?

Answer 14

Mouth, oesophagus, anal canal (entry and exit)

Question 15

Where can you find simple columnar epithelium?

Answer 15

Stomach, small & large intestine

Question 16

What is the function of the epithelium in the digestive tract?

Answer 16

• Barrier separating lumen of alimentary canal from body
• Synthesis and secretion of digestive enzymes, hormones, mucus
• Absorbs products of digestion

Question 17

What is the lamina propria?

Answer 17

•Loose connective tissue (glands, blood/lymph vessels)

Question 18

What is the muscularis mucosae?

Answer 18

Thin smooth muscle layer

Question 19

What type of the tissue is the submucosa?

Answer 19

Thick irregular connective tissue

Question 20

What is the function of the submucosa?

Answer 20

Supports the mucosa

Question 21

What is contained within the submucosa?

Answer 21

Blood vessels, neurones, lymphatic vessels.

The neurones form an extensive network, submucosal plexus (Meissner’s) (parasympathetic)

Question 22

What is the function of the submucosal glands in the oesophagus and the duodenum?

Answer 22

Oesophagus - mucus secretion

Duodenum - bicarbonate secretion to neutralise stomach acid

Question 23

What are the function of the lymphatic vessels in the submucosa?

Answer 23

Take away the products of fat digestion

Question 24

What is the serosa / adventita described as?

Answer 24

A connective tissue sheath surrounding the alimentary canal.

Adventita attaches the oesophagus and rectum to surrounding structures

Serosa surrounds the stomach, small intestine and the large intestine

Question 25

What comprises the enteric nervous system?

Answer 25

The submucosal plexuses and the myenteric plexuses

Question 26

Where can you find myenteric plexus'?

Answer 26

•Myenteric (Auerbach’s) plexus between circular and longitudinal muscle

Question 27

Which parasympathetic nerves are responsible for alimentary nervous control?

Answer 27

Vagus nerve (cranial nerve 10) apart from salivation which is controlled by facial (VII) and glossopharyngeal (IX)

Question 28

What is the effect of the parasympathetic nervous system on the alimentary function?

Answer 28

Stimulatory - an increase in secretion and motility

Question 29

Which sympathetic nerves are responsible for alimentary nervous control?

Answer 29

Splanchnic nerve

Question 30

What is the effect of the sympathetic nervous system on the alimentary function?

Answer 30

Inhibatory (except salivation) There is a decrease in ecretion and motility

Question 31

What do the following arteries supply?

Answer 31

Question 32

How does blood from the stomach reach the inferior vena cava?

Answer 32

Gastric veins - Hepatic portal vein - Hepatic vein - Inferior Vena Cava

Question 33

How does blood from the pancreas reach the inferior vena cava?

Answer 33

Splenic vein - Hepatic portal vein - Hepatic vein - Inferior Vena Cava

Question 34

How does blood from the small intestine, caecum, ascending colon and the transverse colon reach the inferior vena cava?

Answer 34

Superior mesenteric vein - hepatic portal vein - hepatic vein - IVC

Question 35

How does blood from the descending colon, sigmoid colon and the rectum reach the IVC?

Answer 35

Inferior mesenteric vein - Hepatic portal vein - hepatic vein - IVC

Question 36

Which organs send blood to the liver?

Answer 36

The heart for oxygen supply - hepatic artery Those which supply the hepatic portal vein (digestive tract arteries) - these include the stomach, intestines, pancreas and spleen