Loss of water from the plant body takes place through :

Question

Accepted Answer

Loss of water from the plant body primarily occurs through two main processes: transpiration and guttation. Option 3, which states that water loss occurs through "Stomata and hydathodes," is the correct answer. Here's a detailed explanation supporting this:

1. **Stomata**: These are small openings found on the surface of leaves, primarily on the underside. They play a crucial role in the process of transpiration, which is the loss of water vapor from the plant to the atmosphere. Stomata open and close to regulate gas exchange and water loss. During the day, when stomata are open, water vapor escapes from the plant, contributing significantly to water loss.

2. **Hydathodes**: These are specialized structures located at the margins or tips of leaves. They are involved in the process of guttation, which is the exudation of liquid water from the plant. Guttation typically occurs at night or in the early morning when soil moisture is high, and transpiration is low. Hydathodes release water droplets, which is another form of water loss from the plant body.

Now, let's examine why the other options are incorrect:

1. **Option 1: Stomata, cell wall of mesophyll cells, and hydathodes** - While stomata and hydathodes are indeed involved in water loss, the cell wall of mesophyll cells is not a direct pathway for water loss. Mesophyll cells are involved in photosynthesis and gas exchange, but water loss through their cell walls is not a significant or recognized process.

2. **Option 2: Stomata and cell wall of mesophyll cells** - This option correctly identifies stomata as a pathway for water loss but incorrectly includes the cell wall of mesophyll cells. As mentioned earlier, the cell wall of mesophyll cells is not a primary or significant pathway for water loss.

3. **Option 4: Cell wall of mesophyll cells and hydathodes** - This option correctly identifies hydathodes as a pathway for water loss but incorrectly includes the cell wall of mesophyll cells. Without the inclusion of stomata, this option fails to account for the primary mechanism of water loss through transpiration.

In conclusion, Option 3 is the correct answer because it accurately identifies the two main pathways for water loss from the plant body: stomata, through transpiration, and hydathodes, through guttation.