Advanced Zona Reticularis Quiz

Q1. Why is DHEA sulfate an important product associated with zona reticularis steroidogenesis?

• It stores DHEA inside catecholamine granules
• It converts DHEA directly into aldosterone
• It converts DHEA into epinephrine
• Sulfation produces a major circulating adrenal androgen precursor

Q2. How does cytochrome b5 support adrenal androgen production in zona reticularis cells?

• It inhibits all steroidogenesis
• It converts norepinephrine to epinephrine
• It functions as the ACTH receptor
• It enhances CYP17A1 17,20-lyase activity

Q3. Why is the zona reticularis better suited for adrenal androgen production than the zona glomerulosa?

• It lacks mitochondria
• It is the only cortical zone supplied by blood
• It contains chromaffin granules
• Its enzyme profile supports 17-hydroxylated steroid and androgen synthesis

Q4. Why can prolonged ACTH suppression lead to zona reticularis atrophy?

• Loss of ACTH trophic stimulation can cause atrophy
• Suppressed ACTH increases reticularis cell division
• ACTH normally destroys the reticularis
• The reticularis is regulated only by potassium

Q5. Why can chronic ACTH excess enlarge the zona reticularis?

• ACTH removes all reticularis cells
• Persistent ACTH can cause hypertrophy and hyperplasia
• ACTH affects only the adrenal capsule
• ACTH converts the zone into renal cortex

Q6. How does the zona reticularis relate spatially to corticomedullary blood flow?

• It lies outside the adrenal vascular supply
• It receives blood only after the central vein
• It is the final cortical zone traversed before blood reaches the medulla
• It drains directly into the renal pelvis

Q7. Why can lipofuscin become conspicuous in zona reticularis cells?

• It accumulates as intracellular residual pigment with cellular aging
• It is stored aldosterone
• It is newly synthesized melanin
• It is precipitated calcium from urine

Q8. What developmental event is associated with functional maturation of the zona reticularis?

• Neurulation
• Closure of the ductus arteriosus
• Gastrulation only
• Adrenarche

Q9. Why can disorders causing excess adrenal androgen production have systemic effects?

• Androgens remain confined beneath the adrenal capsule
• The hormones enter the renal pelvis and act only on urine
• Steroid products enter the circulation and act on distant tissues
• The reticularis sends motor axons throughout the body

Q10. Which statement best integrates zona reticularis anatomy and function?

• It is neural crest-derived chromaffin tissue producing catecholamines
• It is the outermost cortical zone specialized for aldosterone synthesis
• It is an ACTH-responsive inner cortical network specialized for adrenal androgen synthesis
• It is an avascular fibrous boundary between the kidney and adrenal gland