Question

Which one of the following has the lowest cuticular transpiration?

• A. Helianthus
• B. Sorghum
• C. Opuntia
• D. Hordeum

Hint:

Plant adaptations:
- Xerophytes: Thick cuticle (e.g., Opuntia).
- Hydrophytes: Thin cuticle.
- Mesophytes: Moderate cuticle.

Answer 1

The Correct Option is C

Step 1: Understanding the Question:
This question tests knowledge of water loss mechanisms in plants.

Step 2: Detailed Explanation:
Cuticular transpiration is the loss of water through the cuticle of leaves.
Opuntia (Cactus) has a thick waxy cuticle to minimize water loss.
It is a xerophyte adapted to arid conditions.
Helianthus (A): Sunflower, moderate cuticular transpiration.
Sorghum (B): Has some drought tolerance but not as low as Opuntia.
Hordeum (D): Barley, moderate transpiration.
Thus, Opuntia has the lowest cuticular transpiration.

Step 3: Final Answer:
Thus, Opuntia has the lowest cuticular transpiration, which corresponds to option (C).
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