MOH Anatomy & Physiology 2 — Questions and Answers
Question 1: Which cranial nerve is tested when checking the gag reflex?
- CN V and CN VII
- CN IX (glossopharyngeal) and CN X (vagus) (Correct answer)
- CN XII only
- CN VII and CN IX
Correct answer: CN IX (glossopharyngeal) and CN X (vagus)
The afferent limb of the gag reflex is CN IX (glossopharyngeal) and the efferent motor response is mediated by CN X (vagus), together testing the integrity of the brainstem.
Question 2: Cerebrospinal fluid (CSF) is primarily produced by:
- Arachnoid villi
- Choroid plexus (Correct answer)
- Ependymal cells of the spinal cord
- Dural sinuses
Correct answer: Choroid plexus
The choroid plexus, located within the ventricles of the brain, produces approximately 500 mL of CSF per day by active secretion and ultrafiltration of plasma.
Question 3: Normal adult tidal volume is approximately:
- 150 mL
- 500 mL (Correct answer)
- 1200 mL
- 2500 mL
Correct answer: 500 mL
Normal adult tidal volume — the amount of air inhaled or exhaled in a single resting breath — is approximately 500 mL (7 mL/kg of ideal body weight).
Question 4: The portal vein is formed by the union of which two vessels?
- Splenic vein and inferior mesenteric vein
- Superior mesenteric vein and splenic vein (Correct answer)
- Inferior mesenteric vein and hepatic vein
- Splenic vein and left gastric vein
Correct answer: Superior mesenteric vein and splenic vein
The portal vein is formed by the confluence of the superior mesenteric vein and the splenic vein behind the neck of the pancreas, draining nutrient-rich blood to the liver.
Question 5: Insulin is secreted by which cells of the pancreatic islets of Langerhans?
- Alpha cells
- Delta cells
- Beta cells (Correct answer)
- PP (F) cells
Correct answer: Beta cells
Beta cells of the islets of Langerhans secrete insulin in response to elevated blood glucose, promoting glucose uptake by cells and reducing blood sugar levels.
Question 6: Which structure passes through the carpal tunnel alongside the flexor tendons?
- Ulnar nerve
- Radial nerve
- Median nerve (Correct answer)
- Radial artery
Correct answer: Median nerve
The median nerve passes through the carpal tunnel along with nine flexor tendons; compression of this nerve causes carpal tunnel syndrome characterized by thenar wasting and palmar paresthesias.
MOH Anatomy & Physiology 2
Which cranial nerve is tested when checking the gag reflex?