Q- A child has chronic diarrhea and failure to thrive. Stool is positive for fat. The sweat chloride test is elevated.
Which mechanism explains the GI symptoms?
A- Decreased pancreatic enzyme secretion
B- Increased bile acid synthesis
C- Increased gastric acid production
D- Increased intestinal chloride secretion
Q- A patient has progressive weakness and ptosis that improves with rest. Autoantibodies are directed against postsynaptic acetylcholine receptors.
Which finding is expected?
A- Decreased ACh release at presynaptic terminal
B- Decreased muscle action potential amplitude with repeated stimulation
C- Increased AChE activity
D- Increased thymic mass
Q- A man presents with episodic palpitations, headache, and sweating. Urine shows elevated metanephrines.
The tumor most likely arises from which embryologic tissue?
A- Endoderm
B- Mesoderm
C- Neural crest
D- Surface ectoderm
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