In which of the following the rate of transpiration is high

Options

A. CAM Plant
B. `C_(3)` plants
C. `C_(3) and C_(4)`
D. `C_(4)` plants

Answer

**Step-by-Step Solution:**

1. **Understanding Transpiration:**
- Transpiration is the process by which excess water is lost from the plant to the environment, primarily through the leaves. It is similar to excretion in humans and occurs mainly through small openings called stomata.

2. **Factors Affecting Transpiration:**
- The rate of transpiration is influenced by the opening and closing of stomata. When stomata are open, water vapor can escape, leading to higher transpiration rates.

3. **Identifying Plant Types:**
- The question provides different types of plants: CAM plants, C3 plants, and C4 plants. We need to analyze each type to determine which has the highest rate of transpiration.

4. **Analyzing CAM Plants:**
- CAM (Crassulacean Acid Metabolism) plants are adapted to arid environments (e.g., cacti, pineapple). They have a very low transpiration rate because they open their stomata at night to minimize water loss during the day. Therefore, CAM plants are excluded from having a high transpiration rate.

5. **Analyzing C3 Plants:**
- C3 plants are the most common type of plants (about 85% of all plants). They require the stomata to be open to take in carbon dioxide for photosynthesis. This leads to a high transpiration rate as water vapor escapes when the stomata are open.

6. **Analyzing C4 Plants:**
- C4 plants have a different mechanism for photosynthesis that separates light-dependent reactions and the Calvin cycle. While they have a normal rate of transpiration, it is not as high as that of C3 plants.

7. **Conclusion:**
- After analyzing all three types of plants, we conclude that C3 plants have the highest rate of transpiration.

**Final Answer:**
The plant in which the rate of transpiration is high is **C3 plants**.

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