GI ILA formatives

Question 1

secreted by D cells; inhibit acid production

Answer 1

Somatostatin

Question 2

secreted by enterochromaffin cells; stimulates acid production

Answer 2

histamine

Question 3

Secreted by G cells; stimulates acid production

Answer 3

gastrin

Question 4

Secreted by Cheif cells; no effect on acid production

Answer 4

pepsinogen

Question 5

What is the main defence mechanism of gastric cells against damage by acid?

Answer 5

Mucus from goblet cells

Question 6

How do aspirin & NSAIDs irritate the stomach?

Answer 6

By decreasing mucus synthesis through inhibition of prostaglandin production

Question 7

What is the lower oesophageal sphincter?

Answer 7

• circular muscle of the gastro-oesophageal wall
• the acute angle made by the esophagus entering the stomach
• A motility pattern due to innervation from the vagus nerve branches from oesophagus down to the stomach
• The diaphragm

Question 8

On prolonged exposure to acid, the cells of the lower oesophagus undergo metaplasia (reversible change from one cell to another). What does the epithelium change from and to?

Answer 8

stratified squamous to columnar

Question 9

What is the action of the proton pump on the parietal cells of the stomach?

Answer 9

K+into cell, H+ out of cell

Question 10

We are currently trying to design a drug that acts on histamine receptors on parietal cells to help patients with reflux disease. what would be the mechanism of this drug?

Answer 10

Inhibits Histamine 2 receptors to reduce acid secretion. (H2 found in gastric mucosa, H1 found in smooth muscle ie. Type 1 hypersensitivity in the lungs)

Question 11

Describe the Vagal nerve action on parietal cells.

Answer 11

Vagus nerve is part of the parasympathetic system and releases acetylcholine onto parietal cells which stimulates acid secretion in the cephalic phase

Question 12

which of the following is not a factor to develop reflux?
A. obesity 
B. Sedentary lifestyle (being bare lazy)
C. Pregnancy 
D. hiatal hernia
E. Smoking

Answer 12

Sedentary lifestyle

Question 13

What lies at the junction of the Right mid-clavicular line and the costal margin?

Answer 13

Gall bladder

Question 14

What structure terminates at ampulla of Vater?

Answer 14

Common bile duct

Question 15

Obstructive jaundice can be caused by gall stones within what structure?
A. Pancreas
B.  cystic duct
C. Gall bladder
D. right hepatic 
E. Common bile duct

Answer 15

Common bile duct

Question 16

What is situated within the duodenal loop?

Answer 16

Pancreas - more specifically the pancreatic head

Question 17

microsomal enzyme uridine diphosphoglucourysl transferase (glucuronyl transferase UDPGT) catalyses the formation of what?

Answer 17

conjugated billirubin

Question 18

bacterial enzyme hydrolysis in the gut produces a compound which is excreted in faeces….

Answer 18

stercobilinogen

Question 19

which compound is returned to the liver by the enterohepatic circulation?

Answer 19

urobilinogen

Question 20

absence of which compound causes pale stool in obstructive jaundice?

Answer 20

stercobilinogen

Question 21

A 40 yr old chronic alcoholic come with c/o yellow discolouration of skin and an acutely painfu abdomen; he is thought to have acute pancreatitis. where does pain typically radiate in this condition?

Answer 21

Back

Question 22

What are the levels of conjugated and unconjugated in the blood in a patient with pre-hepatic jaundice?

Answer 22

Normal conjugated

raised unconjugated

Question 23

a diagnosed carcinoma in the head of the pancreas. What structure is affected to cause jaundice?

Answer 23

Common Bile duct

Question 24

What is the cause of physiological jaundice of a newborn?

Answer 24

Excess breakdown of fetal haemoglobin

Question 25

What causes increased serum bilirubin without any excess bilirubin in the urine?

Answer 25

Pre-hepatic jaundice

Question 26

What is the central structure in a hepatic lobule

Answer 26

hepatic vein

Question 27

Which cell is part of the reticuloendothelial system in the liver?

Answer 27

Kupffer cell (reticuloendothelial system - another name for machrophage system)

Question 28

which of the following statements concerning salivary glands is true?

• Parotid gland secretions contain amylase
• salivary duct epithelial cells secrete Na+ and Cl-
• saliva is hypertonic
• the amount of saliva produced varies by race
• the parotid gland continuously produces saliva

Answer 28

Parotid gland secretions contain amylase.

(Amylase is produced by serous cells within salivary gland acini - as are found in the parotid. Salivary duct epithelial cells absorb Na+ and Cl-, rendering saliva hypotonic. A number of factors affect the rate of salivary secretion, but race isnt one of them. The submandibular, submental and minor salivary glands are continuously active but the parotid is not)

Question 29

which of the following is not derived from endoderm?

• hepatocytes
• gut epithelial cells
• pancreatic endocrine cells
• pancreatic exocrine cells
• Smooth muscle in musculuaris propria of the gut

Answer 29

Smooth muscle in musculuaris propria of the gut actually derived from mesoderm

Question 30

what causes the 3 indentations on a barium swallow?

Answer 30

Aortic arch
Left main bronchus
Left Atrium

Question 31

which of the following statements about intestinal mucosa is true?

• Brunners glands are present in the sigmoid colon
• ascending colonic mucosa contains Paneth cells
• Peyer’s patches are present in the submucosa of the ileum
• stem cells are present in the tips of small intestinal villi
• transverse colonic mucosa has villous architecture

Answer 31

Peyer’s patches are present in the submucosa of the ileum.

The mucosa of the various parts of the large intestine and rectum are identical. It lacks villi and Paneth cells (these are features of small intestinal mucosa).

Brunner’s glands are found only in the duodenum.

Peyer’s patches are found in the submucosa, and may extend into the mucosa.

Stem cells are present in the crypts of Lieberkuhn, not the tips of the villi.