Which of the following is not an adaptation in desert plants to conserve water?

Options

A. Presence of stomata in deep pits
B. CAM pathway to enable the stomata to remain closed during night time
C. Reduction of leaves into spines to minimise the loss of water through transpiration
D. Thick cuticle on the leaf surfaces

Answer

To solve the question "Which of the following is not an adaptation in desert plants to conserve water?", we will analyze the adaptations of desert plants and identify the incorrect option.

### Step-by-Step Solution:

1. **Understand the Question**: We need to identify which option does not represent an adaptation of desert plants for water conservation.

2. **Identify Common Adaptations in Desert Plants**:
- **Thick Cuticles**: Desert plants often have thick cuticles on their leaves to reduce water loss through evaporation and transpiration.
- **Deep Roots**: These plants typically have deep root systems that allow them to access water from deeper soil layers.
- **Reduced Leaf Surface Area**: Many desert plants have leaves that are modified into spines or thorns, which decreases the surface area and thus reduces water loss.
- **Stomata Positioning**: Stomata in desert plants are often located in deep pits or are closed during the day to minimize water loss.
- **CAM Pathway**: Some desert plants use the Crassulacean Acid Metabolism (CAM) pathway, where stomata open at night to fix carbon dioxide, reducing water loss during the hotter daytime.

3. **Evaluate Each Option**:
- If the options include adaptations like thick cuticles, deep roots, reduced leaf surface area, and the CAM pathway, we need to identify which one does not fit as an adaptation for water conservation.

4. **Identify the Incorrect Option**:
- Based on the adaptations discussed, if an option states that stomata are always open during the daytime, this would be incorrect as desert plants typically keep their stomata closed during the day to conserve water.

5. **Conclusion**: The option that states stomata are always open during the daytime is not an adaptation in desert plants to conserve water. Therefore, this is the correct answer to the question.

### Final Answer:
The option that is not an adaptation in desert plants to conserve water is the one that states stomata are always open during the daytime.

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