Question

Following are the misconceptions about root hydrotropism. State whether they are correct or not.
i. The greater growth of roots in moist soil zones than in dry soil zones is not usually a result of hydrotropism. Hydrotropism requires a root to bend from a drier to a wetter soil zone. Roots require water to grow so roots that happen to be in moist soil will grow and branch much more than those in dry soil.
ii. Roots cannot sense water inside intact pipes via hydrotropism and break the pipes to obtain the water.
iii. Roots cannot sense water several feet away via hydrotropism and grow toward it. At best hydrotropism probably operates over distances of a couple millimeters.

• A. (i) and (iii) are correct.
• B. (i) and (ii) are correct.
• C. All are correct.
• D. None of the above are correct.

Answer 1

Answer: (C)

All are correct.

The greater growth of roots in moist soil zones than in dry soil zones is not usually a result of hydrotropism. Hydrotropism requires a root to bend from a drier to a wetter soil zone. Roots require water to grow so roots that happen to be in moist soil will grow and branch much more than those in dry soil.
Roots cannot sense water inside intact pipes via hydrotropism and break the pipes to obtain the water.
Roots cannot sense water several feet away via hydrotropism and grow toward it. At best hydrotropism probably operates over distances of a couple millimeters.

The points given above are true about hydrotropism and it is a common misconception of the same.

Therefore, the correct answer is option C.