Grand Tour of the Alimentary Canal

Question 1

What are some functions of the digestive system?

Answer 1

Digestion

Secretion

Absorption

Motility

Question 2

What is the function of the mouth?

Answer 2

Break down foodstuff by chewing, saliva acting as a lubricant

Question 3

What is the function of the oesophagus?

Answer 3

Conduit between the mouth and stomach

Question 4

What is the function of the stomach?

Answer 4

Digestion of proteins

Foodstuff reduced to liquid form

Storage

Sterilisation

Question 5

What is the function of the pancreas?

Answer 5

Digestive enzymes for digestion of fats, carbohydrates and proteins

Question 6

What is the function of the liver?

Answer 6

Produce bile salts for digestion/absorption of fats in the small intestine

Question 7

What is the function of the gallbladder?

Answer 7

Stores and concentrates bile

Question 8

What is the function of the small intestine?

Answer 8

Final stages of chemical digestion and nutrient absorption

Question 9

What is the function of the large intestine?

Answer 9

Water absorption

Bacterial fermentation and formation of faeces

Question 10

In basic terms what is the alimentary canal?

Answer 10

Continuous hollow tube from the oesophagus to the rectum

Question 11

How long is the alimentary canal?

Answer 11

About 8m long

Question 12

What can be said about the structural formation of the alimentary canal throughout its length?

Answer 12

It is the same throughout its length with 4 distinct layers

Question 13

What are the 4 distinct layers of the alimentary canal?

Answer 13

Mucosa

Submucosa

Muscularis external

Serosa/adventitia

Question 14

Where is stratified squamous epithelium found?

Answer 14

Mouth

Oesophagus

Anal canal

Question 15

Where is simple columnar epithelium?

Answer 15

Stomach

Small intestine

Large intestine

Question 16

What is the functions of epithelium?

Answer 16

Separate lumen of alimentary canal from the body

Synthesis and secretion of digestive enzymes, hormones and mucus

Absorbs products of digestion

Question 17

What are the layers of the mucosa?

Answer 17

Epithelium

Lamina propria

Muscularis mucosae

Question 18

What is lamina propria?

Answer 18

Loose connective tissue (glands, blood and lymph vessels)

Question 19

What is muscularis mucosae?

Answer 19

Thin smooth muscle layer

Question 20

What is submucosa?

Answer 20

Thick, irregular connective tissue to support mucosa

Question 21

What does the submucosa contain?

Answer 21

Nuerons

Blood vessels

Lymphatic vessels

Question 22

What do neurons form in the submucosa?

Answer 22

Submucosal plexus (parasympathetic)

Question 23

Is the submucosal plexus sympathetic or parasympathetic?

Answer 23

Parasympathetic

Question 24

Where are submucosal glands found?

Answer 24

Oesophagus

Duodenum

Question 25

What makes up the muscularis externa?

Answer 25

Two concentric thick layers of smooth muscles (inner layer and outer layer)

Question 26

What is the inner layer of the muscularis externa?

Answer 26

Circular muscle

Question 27

What is the outer layer of the muscularis externa?

Answer 27

Longitudinal muscle

Question 28

What is the function of the circular muscle?

Answer 28

Constrict lumen

Question 29

What is the function of the longitudinal muscle?

Answer 29

Shortens tube

Question 30

What is the function of the muscularis externa?

Answer 30

Produce motility for peristalsis and segmentation

Question 31

What is found between the circular and longitudinal muscle?

Answer 31

Myenteric plexus

Question 32

What is the enteric nervous system (ENS) formed from?

Answer 32

Submucosal and myenteric plexuses

Question 33

What does the enteric nervous system (ENS) allow?

Answer 33

Independent control of gut function

Question 34

What is the purpose of the adventitia outside of the peritoneum cavity?

Answer 34

Attaches oesophagus and rectum to surrounding structures

Question 35

What is the difference between serosa and adventitia?

Answer 35

Serosa covers organs that freely move inside of a cavity Adventitia bounds organs to supporting structures

Question 36

What kind of tissue is the serosa/adventitia?

Answer 36

Connective tissue

Question 37

What does serosa surround inside the peritoneal canal?

Answer 37

Stomach Small intestine Large intestine

Question 38

What provides autonomic control of alimentary function?

Answer 38

Long (parasympathetic) and short (ENS) reflexes

Question 39

What provides parasympathetic innervation to alimentary function?

Answer 39

Vagus nerve (except salivation which is controlled by facial [VII] and glossopharyngael [IX] nerve

Question 40

What nerves control salivation?

Answer 40

Facial (VII) cranial nerve Glossopharyngeal (IX) cranial nerve

Question 41

What effect does the parasympathetic nervous system have on alimentary function?

Answer 41

Increases secretion and motility

Question 42

What provides sympathetic innvervation to alimentary function?

Answer 42

Thoracic splanchnic nerves

Question 43

What effect does sympathetic innervation have on the alimentary function?

Answer 43

Decreases secretion and motility (except salivation)

Question 44

What 3 main arteries supply the GI tract?

Answer 44

Celiac trunk Superior mesenteric artery Inferior mesenteric artery

Question 45

What do the celiac trunk, superior mesenteric and inferior mesenteric branch from?

Answer 45

Abdominal aorta

Question 46

What does the celiac trunk artery supply?

Answer 46

Stomach Small intestine Pancreas Liver

Question 47

What does the superior mesenteric artery supply?

Answer 47

Small intestine Caecum Ascending colon Transverse colon

Question 48

What does the inferior mesenteric artery supply?

Answer 48

Descending colon Sigmoid colon Rectum

Question 49

What veins drain the stomach?

Answer 49

Gastric veins

Question 50

What veins drain pancreas?

Answer 50

Splenic vein

Question 51

What does the superior mesenteric vein drain?

Answer 51

Small intestine Caecum Ascending colon Transverse colon

Question 52

What does inferior mesenteric vein drain?

Answer 52

Decending colon Sigmoid colon Rectum

Question 53

What veins drain into the hepatic portal vein?

Answer 53

Gastric veins Splenic vein Superior mesenteric vein Inferior mesenteric vein

Question 54

What is the venous drainage from the hepatic portal vein?

Answer 54

Hepatic portal vein -\> hepatic vein -\> inferior vena cava