TOPOGRAPHY OF THE ORAL CAVITY, OESOPHAGUS AND STOMACH

Question 1

What is the digestive system composed of?

Answer 1

• GI tract/ alimentary canal
• Accessory digestive organs

Question 2

What is the alimentary canal?

Answer 2

Muscular tube that winds through the body extending from the mouth to the anus

Question 3

Which organs make up the alimentary canal in sequential order? (14)

Answer 3

• Oral cavity
• Pharynx
• Oesophagus
• Stomach
• Duodenum
• Jejunum
• Ileum
• Cecum
• Ascending colon
• Transverse colon
• Descending colon
• Sigmoid colon
• Rectum
• Anal canal

Question 4

What are the accessory digestive organs?

Answer 4

• Teeth
• Tongue
• Salivary glands - connected to alimentary canal via ducts
• Liver
• Gall bladder
• Pancreas - connected to alimentary canal via ducts

Question 5

What does the digestive system supply the body with?

Answer 5

• Continuous supply of water
• electrolytes
• vitamins
• nutrients

Question 6

What are the 6 essential food processing activities of the digestive system?

Answer 6

• ingestion
• propulsion
• mechanical digestion
• digestion
• absorption
• defacation

Question 7

What is ingestion?

Answer 7

The uptake of food into the mouth

Question 8

What is propulsion?

Answer 8

The movement of food through the alimentary canal. It includes voluntary and involuntary movements of swallowing and peristalsis

Question 9

What is mechanical digestion?

Answer 9

Process by which morsels of food are mechanically broken down in size in preparation for digestion by enzymes. It begins in the mouth during chewing and continues in the stomach during churning of food.

Question 10

What is digestion?

Answer 10

Multistep process that results in the formation of basic chemical substrates. Carbs, proteins, lipids and nucleic acids are broken down into their chemical building blocks

Question 11

What is absorption?

Answer 11

The final stage of transporting basic molecules from the luminal cavity to the destination organs

Question 12

What is defecation?

Answer 12

The elimination of waste and undigested matter in the form of faeces

Question 13

Which bones contribute to the skeletal framework of the oral cavity?

Answer 13

• The mandible or the lower Jaw bone
• The maxilla or the upper jaw bone
• The palatine bones

Question 14

What are the 3 salivary glands and which ones are palpable?

Answer 14

• Submandibular
• Sublingual
• Parotid

The submandibular and the parotid are palpable

Question 15

What are the intrinsic muscles of the tongue?

Answer 15

• Superior longitudinal
• Vertical
• Transverse
• Inferior longitudinal
• Septum

Question 16

What are the 3 areas of constriction in the oesophagus?

Answer 16

• Cervical constriction at the pharyngoesophageal junction
• Thoracic at the broncho - aortic level
• Diaphragmatic

Question 17

What vertebral levels does the oesophagus start and end at?

Answer 17

Starts at C6 and crosses the diaphragm at C10

Question 18

What 6 structures are derived from the foregut?

Answer 18

• Stomach
• Gall bladder
• Liver
• Pancreas
• Spleen
• First half of the duodenum

Question 19

What 6 structures are derived from the midgut?

Answer 19

• The distal half of the duodenum
• Jejunum
• Ileum
• Cecum
• Ascending colon
• The proximal half of the transverse colon

Question 20

What 4 structures are derived from the hindgut?

Answer 20

• The distal half of the transverse colon
• Descending colon
• Sigmoid colon
• The proximal third of the rectum

Question 21

Which arteries supply the midgut and hindgut?

Answer 21

• Midgut = Superior mesenteric artery
• Hindgut = Inferior mesenteric artery