Histology Certification Organ Histology 2 — Questions and Answers
Question 1: Which layer of the adrenal cortex produces mineralocorticoids such as aldosterone?
- Zona glomerulosa (Correct answer)
- Zona fasciculata
- Zona reticularis
- Adrenal medulla
Correct answer: Zona glomerulosa
The zona glomerulosa is the outermost cortical layer and is the sole site of mineralocorticoid synthesis.
Question 2: The hepatic sinusoids are lined by which specialized cell type that lacks a basement membrane?
- Kupffer cells
- Ito cells
- Sinusoidal endothelial cells (Correct answer)
- Hepatocytes
Correct answer: Sinusoidal endothelial cells
Sinusoidal endothelial cells (LSECs) line hepatic sinusoids and are fenestrated without a continuous basement membrane, facilitating exchange.
Question 3: In the kidney, which structure separates the glomerular capillary lumen from the Bowman's space?
- Macula densa
- Filtration barrier (endothelium, GBM, podocytes) (Correct answer)
- Peritubular capillary wall
- Juxtaglomerular apparatus
Correct answer: Filtration barrier (endothelium, GBM, podocytes)
The filtration barrier consists of fenestrated endothelium, glomerular basement membrane, and podocyte foot processes with slit diaphragms.
Question 4: The interalveolar septa of the lung contain type II pneumocytes whose primary function is to:
- Phagocytose inhaled particles
- Produce surfactant (Correct answer)
- Facilitate gas exchange
- Transport oxygen across the barrier
Correct answer: Produce surfactant
Type II pneumocytes contain lamellar bodies and secrete pulmonary surfactant to reduce alveolar surface tension.
Question 5: Which histological feature distinguishes the pyloric glands of the stomach from the fundic glands?
- Presence of chief cells
- Abundance of parietal cells
- Predominantly mucous secretory cells with few parietal cells (Correct answer)
- Presence of enterochromaffin-like cells
Correct answer: Predominantly mucous secretory cells with few parietal cells
Pyloric glands are composed mainly of mucous cells and are nearly devoid of the chief and parietal cells that dominate fundic glands.
Question 6: The thyroid follicle is filled with colloid, which stores which precursor molecule?
- Calcitonin
- Thyroglobulin (Correct answer)
- Parathyroid hormone
- Triiodothyronine
Correct answer: Thyroglobulin
Thyroglobulin is the glycoprotein stored in follicular colloid and serves as the precursor for thyroid hormone synthesis.
Question 7: Which zone of the liver acinus (Rappaport) is most susceptible to ischemic necrosis due to its distance from the portal triad?
- Zone 1
- Zone 2
- Zone 3 (Correct answer)
- Periportal zone
Correct answer: Zone 3
Zone 3 hepatocytes, located closest to the central vein, receive the least oxygenated blood and are most vulnerable to ischemia.
Histology Certification Organ Histology 2
Which layer of the adrenal cortex produces mineralocorticoids such as aldosterone?