Question

Reabsorption in tubules of nephrons occurs by

• A. Osmosis
• B. Diffusion
• C. Active transport
• D. Both B and C

Answer 1

The correct option is D Both B and C

The volume of the filtrate formed per day (180 liters) with that of the urine released (1.5 liters) suggests that nearly 99% of the filtrate gets reabsorbed by the renal tubules. This process is called as reabsorption. The tubular epithelial cells in different segments of nephron perform this either by active or passive mechanism. Substances like glucose, amino acids, $N{a}^{+}$ etc. in the filtrate are reabsorbed actively, whereas the nitrogenous wastes are absorbed by passive transport. Reabsorption of water occurs passively in the initial segments of the nephron.

Therefore, the correct answer is option D.