Tour of the Alimentary Canal

Question 1

What are the 4 main aspects of the digestive system ?

Answer 1

Digestion
Secretion
Absorption
Motility

Question 2

What physiological processes occur in the mouth ?

Answer 2

The saliva within the mouth breaks down large molecules into smaller more digestible ones.

Question 3

What physiological processes occur in the stomach ?

Answer 3

Digestion of proteins, reduction of food to liquid form and storage of the digested materials.

Question 4

Enzymes from the pancreas assist in digestion of ___, ____ and _____

Answer 4

fats, carbs and proteins

Question 5

What is released from the gallbladder/liver to assist with digestion ? and where is this released ?

Answer 5

Bile salts

2nd part of the duodenum through the papilla

Question 6

Where in the Alimentary system are 95% of nutrients absorbed ?

Answer 6

The small intestine

Question 7

What physiological processes occur in the large intestine ?

Answer 7

Water absorption, bacterial fermentation and the formation of faeces

Question 8

What are the four layers of the gut tube ?

Answer 8

Mucosa
Submucosa
Muscularis
Serosa

Question 9

What is the histology of the mucosa layer ?

Answer 9

Stratified squamous epithelium

Question 10

What kind of epithelium is found within the mouth, oesophagus & anal canal ?

Answer 10

Stratified squamous epithelium

Question 11

What type of epithelium is found within the stomach, small intestine and large intestine ?

Answer 11

Columnar epithelium

Question 12

In which layer of the gut tube are glands, nerves and the blood supply ?

Answer 12

Submucosa

Question 13

Which layer of the gut tube is responsible for peristalsis ?

Answer 13

The muscularis layer

Question 14

Where is the myenteric plexus found ?

Answer 14

Between the circular layer and the longitudinal layer of muscle within the wall of the gut tube

Question 15

Where does parasympathetic input come from in the alimentary canal ?

Answer 15

The vagus nerve (Cranial nerve X)

Question 16

What nerves control saliva secretion in parasympathetic input ?

Answer 16

The facial nerve (Cranial nerve VII) and the glossopharyngeal nerve (cranial nerve IX)

Question 17

How is sympathetic input directed to the alimentary canal ?

Answer 17

Via splanchnic nerves

Question 18

What happens to secretions and motility in sympathetic input within the alimentary canal ?

Answer 18

Sympathetic is inhibitory within the alimentary system therefore secretions decrease as does motility

Question 19

What happens to secretions and motility in parasympathetic input within the alimentary canal ?

Answer 19

Parasympathetic is excitatory within the alimentary system therefore secretions will increase as does motility

Question 20

What are the 3 main arterial branches that supply the gut ?

Answer 20

The celiac trunk
The superior mesenteric artery
The inferior mesenteric artery

Question 21

How is the venous blood drained from the alimentary system ?

Answer 21

Through the portal system through the liver

Question 22

Chewing is controlled by which 2 processes ?

Answer 22

Voluntary: Somatic nerves (skeletal muscles in the mouth and jaw)
Reflexes: Contraction of the jaw muscles and the mechanoreceptors that sense food within the mouth.

Question 23

Sympathetic input to the saliva glands will produce what ?

Answer 23

A small amount of thick, viscous saliva.

High mucous and high amylase content

Question 24

Parasympathetic input to the saliva glands will produce what ?

Answer 24

Profuse watery saliva