A patient with a known history of PUD presents with sudden, severe epigastric pain and vomiting. The nurse suspects a perforation. What diagnostic test should be performed immediately?

Correct Answer: D

Rationale: A CT scan quickly confirms perforation by detecting free air or fluid.

Correct Answer: C

Rationale: Gastrin stimulates gastric acid secretion and secretin stimulates bicarbonate-rich pancreatic secretion. CCK-PZ both stimulates gallbladder contraction and pancreatic enzyme secretion. Hydrogen potassium ATPase is an enzyme which determines the activity of the gastric proton pump. Though VIP excess is known to cause Verner-Morrison syndrome (watery diarrhoea, hypokalaemia, and achlorhydria) its role in health is doubtful.

Correct Answer: C

Rationale: Proteins are broken down into amino acids during digestion, as enzymes like pepsin and trypsin hydrolyze peptide bonds. Starch breaks into sugars (not amino acids), and proteins don't yield sugars.

Correct Answer: A

Rationale: The gullet (esophagus) is the tube connecting the mouth to the stomach, making A correct. The rectum and intestines (C, D) are later in the digestive tract.

Correct Answer: A

Rationale: Structure X is likely the liver or gallbladder (based on typical diagrams), secreting bile to emulsify fats, increasing their surface area for digestion, making A correct.