The Grand Tour of the Alimentary Canal

Question 1

GI tract

Answer 1

series of hollow organs joined in a long, twisting tube from the mouth to the anus

Question 2

what makes up the GI tract

Answer 2

mouth, oesophagus, stomach, small intestine, large intestine, and anus

Question 3

accessory organs

Answer 3

salivary glands, liver, pancreas, gallbladder

Question 4

main functions of digestive system

Answer 4

digestion, secretion, absorption, motility

Question 5

digestion

Answer 5

breaking down of the food we eat into simple substances that our bodies can absorb

Question 6

Digestive absorption

Answer 6

passage of the end products of digestion from the gastrointestinal tract into the blood, and lymphatic vessels.

Question 7

secretion

Answer 7

process by which substances are produced and discharged from a cell, gland, or organ for a particular function in the organism or for excretion.

Question 8

motility

Answer 8

ability of an organism to move independently, using metabolic energy.

Question 9

What is the function of the mouth?

Answer 9

Break down foodstuff by chewing, saliva acting as a lubricant

Question 10

What is the function of the oesophagus?

Answer 10

Conduit between the mouth and stomach

Question 11

What is the function of the stomach?

Answer 11

Digestion of proteins

Foodstuff reduced to liquid form

Storage

Sterilisation

Question 12

What is the function of the pancreas?

Answer 12

Digestive enzymes for digestion of fats, carbohydrates and proteins

Question 13

What is the function of the liver?

Answer 13

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

Question 14

What is the function of the gallbladder?

Answer 14

Stores and concentrates bile

Question 15

What is the function of the small intestine?

Answer 15

Final stages of chemical digestion and nutrient absorption

Question 16

What is the function of the large intestine?

Answer 16

Water absorption

Bacterial fermentation and formation of faeces

Question 17

In basic terms what is the alimentary canal?

Answer 17

Continuous hollow tube from the oesophagus to the rectum

Question 18

How long is the alimentary canal?

Answer 18

About 8m long

Question 19

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

Answer 19

it is the same throughout its length with 4 distinct layers

Question 20

What are the 4 distinct layers of the alimentary canal?

Answer 20

Mucosa

Submucosa

Muscularis external

Serosa/adventitia

Question 21

Where is stratified squamous epithelium found?

Answer 21

Mouth

Oesophagus

Anal canal

Question 22

Where is simple columnar epithelium?

Answer 22

Stomach

Small intestine

Large intestine

Question 23

What is the functions of epithelium?

Answer 23

Separate lumen of alimentary canal from the body

Synthesis and secretion of digestive enzymes, hormones and mucus

Absorbs products of digestion

Question 24

What are the layers of the mucosa?

Answer 24

mucous epithelium

Lamina propria

Muscularis mucosae

Question 25

What is lamina propria?

Answer 25

Loose connective tissue (glands, blood and lymph vessels)

Question 26

What is muscularis mucosae?

Answer 26

Thin smooth muscle layer

Question 27

What is submucosa?

Answer 27

Thick, irregular connective tissue to support mucosa

Question 28

What does the submucosa contain?

Answer 28

neurons Blood vessels Lymphatic vessels

Question 29

What do neurons form in the submucosa?

Answer 29

Submucosal plexus (parasympathetic)

Question 30

Is the submucosal plexus sympathetic or parasympathetic?

Answer 30

parasympathetic

Question 31

Where are submucosal glands found?

Answer 31

Oesophagus Duodenum

Question 32

What makes up the muscularis externa?

Answer 32

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

Question 33

What is the inner layer of the muscularis externa?

Answer 33

Circular muscle

Question 34

What is the outer layer of the muscularis externa?

Answer 34

Longitudinal muscle

Question 35

What is the function of the circular muscle?

Answer 35

Constrict lumen

Question 36

What is the function of the longitudinal muscle?

Answer 36

Shortens tube

Question 37

What is the function of the muscularis externa?

Answer 37

Produce motility for peristalsis and segmentation

Question 38

What is found between the circular and longitudinal muscle?

Answer 38

Myenteric plexus

Question 39

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

Answer 39

Submucosal and myenteric plexuses

Question 40

What does the enteric nervous system (ENS) allow?

Answer 40

Independent control of gut function

Question 41

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

Answer 41

Attaches oesophagus and rectum to surrounding structures

Question 42

What is the difference between serosa and adventitia?

Answer 42

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

Question 43

What kind of tissue is the serosa/adventitia?

Answer 43

Connective tissue

Question 44

What does serosa surround inside the peritoneal canal?

Answer 44

Stomach Small intestine Large intestine

Question 45

What provides autonomic control of alimentary function?

Answer 45

Long (parasympathetic) and short (ENS) reflexes

Question 46

What provides parasympathetic innervation to alimentary function?

Answer 46

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

Question 47

What nerves control salivation?

Answer 47

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

Question 48

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

Answer 48

Increases secretion and motility

Question 49

What provides sympathetic innvervation to alimentary function?

Answer 49

Thoracic splanchnic nerves

Question 50

What effect does sympathetic innervation have on the alimentary function?

Answer 50

Decreases secretion and motility (except salivation)

Question 51

What 3 main arteries supply the GI tract?

Answer 51

Celiac trunk Superior mesenteric artery Inferior mesenteric artery

Question 52

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

Answer 52

abdminal aorta

Question 53

What does the celiac trunk artery supply?

Answer 53

Stomach Small intestine Pancreas Liver

Question 54

What does the superior mesenteric artery supply?

Answer 54

Small intestine Caecum Ascending colon Transverse colon

Question 55

What does the inferior mesenteric artery supply?

Answer 55

Descending colon Sigmoid colon Rectum

Question 56

What veins drain the stomach?

Answer 56

Gastric veins

Question 57

What veins drain pancreas?

Answer 57

Splenic vein

Question 58

What does the superior mesenteric vein drain?

Answer 58

Small intestine Caecum Ascending colon Transverse colon

Question 59

What does inferior mesenteric vein drain?

Answer 59

Decending colon Sigmoid colon Rectum

Question 60

what veins drain into the hepatic portal vein?

Answer 60

Gastric veins Splenic vein Superior mesenteric vein Inferior mesenteric vein

Question 61

What is the venous drainage from the hepatic portal vein?

Answer 61

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

Question 62

simple epithelial

Answer 62

one cell layer

Question 63

stratified epithelium

Answer 63

many layers

Question 64

stratified squamous

Answer 64

Mouth, oesophagus, anal canal

Question 65

simple columnar

Answer 65

Stomach, small & large intestine

Question 66

Connective tissue outer layer of alimentary canal Outside peritoneal cavity:

Answer 66

Adventitia attaches oesophagus and rectum to surrounding structures

Question 67

Connective tissue outer layer of alimentary canal Inside peritoneal cavity:

Answer 67

Serosa surrounds stomach, small intestine and large intestine

Question 68

Muscularis Externa

Answer 68

Two concentric thick layers of smooth muscle

Question 69

inner layer of muscularis externa

Answer 69

circular muscle (constricts lumen)

Question 70

outer layer of muscularis externa

Answer 70

longitudinal muscle (shortens tube)

Question 71

what type of motility is produced by muscularis externa

Answer 71

peristalsis, segmentation

Question 72

where is Myenteric (Auerbach’s) plexus found

Answer 72

between circular and longitudinal muscle

Question 73

Submucosal + myenteric plexuses =

Answer 73

enteric nervous system (ENS) ⇒ independent control of gut function

Question 74

Autonomic control:

Answer 74

Long (parasympathetic) and short (ENS) reflexes (both afferent and efferent)

Question 75

Parasympathetic

Answer 75

vagus nerve (X)

Question 76

parasympathetic exception

Answer 76

salivation ⇒ facial (VII) and glossopharyngeal (IX) Stimulatory ⇑ secretion ⇑ motility

Question 77

Sympathetic

Answer 77

⇒ splanchnic nerve Inhibitory (except salivation) ⇓ secretion ⇓ motility

Question 78

Celiac trunk

Answer 78

Stomach Small intestine Pancreas Liver

Question 79

Superior mesenteric artery

Answer 79

Small intestine Caecum Ascending colon Transverse colon

Question 80

Inferior mesenteric artery

Answer 80

Descending colon Sigmoid colon Rectum

Question 81

Stomach

Answer 81

Gastric veins

Question 82

Pancreas

Answer 82

Splenic vein

Question 83

Small intestine Caecum Ascending colon Transverse colon

Answer 83

Superior mesenteric vein

Question 84

Descending colon Sigmoid colon Rectum

Answer 84

Inferior mesenteric vein

Question 85

gastric veins, splenic vein, superior mesenteric vein, inferior mesenteric vein

Answer 85

hepatic portal vein

Question 86

hepatic portal vein

Answer 86

hepatic vein

Question 87

hepatic vein

Answer 87

IVC