Q20 / 200 · MHT CET - Medical 2026 (24 April Shift 2) · Biology
Active absorption of water by roots is _____.
- AAlong the DPD gradient and with the expenditure of ATP (energy).
- Correct answerBAgainst the DPD gradient and with the expenditure of ATP (energy).
- CAgainst the DPD gradient and without the expenditure of ATP (energy).
- DAlong the DPD gradient and without the expenditure of ATP (energy).
Solution
Active absorption of water by roots can be of two types: osmotic and non-osmotic.
In non-osmotic active absorption, water is absorbed against the concentration gradient or DPD (Diffusion Pressure Deficit) gradient. Since the movement of water occurs against the natural gradient (i.e., from a region of higher DPD to a region of lower DPD), it requires the direct expenditure of metabolic energy in the form of ATP.
Therefore, active absorption of water by roots is against the DPD gradient and with the expenditure of ATP.
Answer: Against the DPD gradient and with the expenditure of ATP (energy).
In non-osmotic active absorption, water is absorbed against the concentration gradient or DPD (Diffusion Pressure Deficit) gradient. Since the movement of water occurs against the natural gradient (i.e., from a region of higher DPD to a region of lower DPD), it requires the direct expenditure of metabolic energy in the form of ATP.
Therefore, active absorption of water by roots is against the DPD gradient and with the expenditure of ATP.
Answer: Against the DPD gradient and with the expenditure of ATP (energy).
Hence, the correct answer is option: 'B'.