Nokea
Regardless of the precipitating factor
- A. what causes the injury to mucosal cells in peptic ulcers?
- B. Acid back diffusion into the mucosa
- C. The release of histamine from GI cells
- D. Ammonia formation in the mucosal wall
Correct Answer: D
Rationale: Step 1: Peptic ulcers are mainly caused by H. pylori infection or NSAIDs use, not directly related to acid injury.
Step 2: Ammonia formation in the mucosal wall neutralizes acid, protecting mucosal cells.
Step 3: Ammonia is produced by H. pylori urease enzyme, contributing to ulcer formation.
Step 4: Acid back diffusion (B) and histamine release (C) are consequences, not direct causes of ulcers.
Summary: Ammonia formation (D) is the correct answer as it directly contributes to mucosal injury in peptic ulcers. Acid back diffusion (B) and histamine release (C) are secondary effects of ulcer formation, not the primary cause.
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A tumor producing large amounts of the intestinal hormone GIP may result in:
- A. Hyperglycemia
- B. Hypoglycemia
- C. Diarrhea
- D. Intestinal colic
Correct Answer: A
Rationale: The correct answer is A: Hyperglycemia. GIP (gastric inhibitory polypeptide) is released in response to food intake to stimulate insulin release and inhibit glucagon secretion, leading to reduced blood glucose levels. Excessive GIP production from a tumor can result in excessive insulin release, causing hypoglycemia. This is why the correct answer is hyperglycemia. Choices B, C, and D are incorrect as they do not align with the physiological effects of GIP.
If the oesophageal muscles are not working:
- A. Swallowing in the upright position is not affected because of gravity
- B. Water swallowing is not affected
- C. There will be dysphagia to solids and liquids
- D. There will be frequent attacks of vomiting
Correct Answer: C
Rationale: The correct answer is C because if the oesophageal muscles are not working, dysphagia to solids and liquids would occur. This is because the muscles are responsible for peristalsis, which is the wave-like contractions that push food down the esophagus. Choice A is incorrect because gravity alone cannot compensate for muscle dysfunction. Choice B is incorrect as water swallowing also requires proper muscle function. Choice D is incorrect as vomiting is not directly related to oesophageal muscle dysfunction.
Which of these enzymes is responsible for the digestion of lipids?
- A. Amylase
- B. Pepsin
- C. Lipase
- D. Trypsin
Correct Answer: C
Rationale: The correct answer is C: Lipase. Lipase is responsible for the digestion of lipids because it breaks down fats into fatty acids and glycerol. Amylase (A) digests carbohydrates, Pepsin (B) digests proteins, and Trypsin (D) also digests proteins but in the small intestine. Lipase is the only enzyme that specifically targets lipids for digestion, making it the correct choice in this scenario.
A peristaltic rush which results in a failure to absorb enough colon water results in _____.
- A. constipation
- B. diarrhea
- C. cramps
- D. flatus
Correct Answer: B
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Which of these cells in the stomach secrete mucus?
- A. parietal cells
- B. chief cells
- C. mucous neck cells
- D. enteroendocrine cells
Correct Answer: C
Rationale: The correct answer is C: mucous neck cells. These cells secrete mucus to protect the stomach lining from the acidic environment and aid in lubrication. Parietal cells secrete hydrochloric acid, chief cells secrete pepsinogen, and enteroendocrine cells secrete hormones like gastrin. Mucous neck cells are specifically responsible for mucus secretion in the stomach, making them the correct choice.