On a hot summer day cooling of plant occurs due to

Options

A. loss of water vapours from leal
B. transport of water in plant
C. loss of liquid water
D. loss of water from entire plant

Answer

To answer the question "On a hot summer day cooling of plant occurs due to," we can break down the solution into the following steps:

### Step-by-Step Solution:

1. **Understanding the Question**:
- The question asks about the mechanism by which plants cool themselves on hot summer days.

2. **Identifying the Options**:
- The options provided are:
a) Loss of water vapor from the leaf
b) Transport of water in plant
c) Loss of liquid water
d) Loss of water from the entire plant

3. **Analyzing Each Option**:
- **Option a**: Loss of water vapor from the leaf - This process is known as transpiration. During transpiration, water evaporates from the surface of the leaves, which helps in cooling the plant.
- **Option b**: Transport of water in plant - While water transport is essential for various plant functions, it does not directly contribute to cooling.
- **Option c**: Loss of liquid water - This does not specifically refer to the cooling process and is less relevant than transpiration.
- **Option d**: Loss of water from the entire plant - This is a broad statement and does not specifically indicate the cooling mechanism.

4. **Conclusion**:
- The most relevant and accurate option is **a) Loss of water vapor from the leaf**, as this process (transpiration) is responsible for cooling the plant on hot days.

### Final Answer:
The cooling of the plant on a hot summer day occurs due to the **loss of water vapor from the leaf**.

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