Intermediate Adrenal Medulla Quiz

Q1. Which neurotransmitter is released by preganglionic sympathetic fibers onto adrenal chromaffin cells?

• Cortisol
• Acetylcholine
• Norepinephrine
• Dopamine

Q2. Which receptor type on chromaffin cells mediates direct preganglionic sympathetic stimulation?

• Muscarinic receptors exclusively
• Mineralocorticoid receptors
• Beta-2 adrenergic receptors only
• Nicotinic acetylcholine receptors

Q3. Through which nerves do preganglionic sympathetic fibers reach the adrenal medulla?

• Pelvic splanchnic nerves
• Vagus nerves exclusively
• Thoracic splanchnic nerves
• Phrenic nerves exclusively

Q4. What is unusual about the sympathetic pathway to the adrenal medulla?

• All fibers synapse first in the celiac ganglion
• Only postganglionic fibers enter the gland
• The pathway is entirely parasympathetic
• Preganglionic fibers reach chromaffin cells without a prior ganglionic synapse

Q5. How are chromaffin cells typically arranged histologically?

• Long skeletal muscle fascicles
• Follicles filled with colloid
• Clusters or cords around sinusoidal capillaries
• Keratinized sheets

Q6. What is the role of the rich sinusoidal network in the adrenal medulla?

• Rapid entry of catecholamines into blood
• Mechanical filtration of lymph
• Production of cerebrospinal fluid
• Storage of urine

Q7. What is the main venous channel within the adrenal medulla?

• Central adrenal vein
• Portal vein
• Inferior mesenteric vein
• Renal arcuate vein

Q8. Which structural feature is characteristic of the central adrenal vein?

• Stratified squamous epithelium
• Longitudinal smooth muscle bundles
• Cartilage rings
• Skeletal muscle valves

Q9. How does blood from the adrenal cortex influence the medulla?

• It carries urine into the medulla
• It blocks medullary catecholamine synthesis
• It supplies only lymphocytes
• It delivers glucocorticoids to chromaffin cells

Q10. Which enzyme in chromaffin cells is stimulated by high local glucocorticoid concentrations?

• Aldosterone synthase
• Renin
• Phenylethanolamine N-methyltransferase
• Acetylcholinesterase