Question

Which of the following are True with reference to rel tubules and collecting ducts?
A. Glomerular capsule possesses podocytes
B. PCT carries simple cuboidal epithelial cells with microvilli
C. DCT carries cells with receptors for ADH and aldosterone
D. DCT carries simple cuboidal cells with microvilli
E. PCT carries simple squamous epithelial cells

• A. A, B and D Only
• B. A, D and E Only
• C. B, C and D Only
• D. A, B and C Only

Hint:

Nephron Histology:
Bowman's Visceral Layer = Podocytes.
PCT = Simple cuboidal WITH brush border microvilli.
DCT = Simple cuboidal WITHOUT prominent microvilli (responds to ADH & Aldosterone).
Loop of Henle Thin Limb = Simple squamous.

Answer 1

The Correct Option is D

Step 1: Understanding the Question:
The question asks to evaluate histological and physiological statements regarding nephron structures in the mammalian kidney.

Step 2: Key Formula or Approach:
Nephron histology and function:
• Bowman's Capsule: Visceral layer composed of podocytes forming filtration slits.

• Proximal Convoluted Tubule (PCT): Lined by simple cuboidal epithelium with dense microvilli (brush border) for tubular reabsorption.

• Distal Convoluted Tubule (DCT) Collecting Duct: Lined by simple cuboidal cells lacking a prominent brush border; express receptors for Aldosterone and Antidiuretic Hormone (ADH).

Step 3: Detailed Explation:

• Statement A (True): The visceral layer of Bowman's (glomerular) capsule contains specialized epithelial cells called podocytes with pedicels that wrap around glomerular capillaries.

• Statement B (True): The PCT is lined by simple cuboidal epithelial cells with a prominent brush border of microvilli that increases surface area for maximum reabsorption ($\sim 65-70\%$ of filtrate).

• Statement C (True): Cells of the late DCT and collecting duct express nuclear/membrane receptors for Aldosterone (increases $\text{}^+$ reabsorption) and ADH (increases water permeability via aquaporin-2 channels).

• Statement D (False): DCT cells are simple cuboidal but lack prominent microvilli/brush border compared to PCT cells.

• Statement E (False): The PCT is composed of cuboidal, not simple squamous, epithelium (simple squamous is found in thin limbs of Henle's loop).

Step 4: Fil Answer:
Statements A, B, and C are correct, making Option (D) the correct answer.