Root pressure is unable to explain the ascent of sap because it is not found in

Options

A. Bryophytes
B. All plants in all seasons
C. Trees
D. Spring.

Answer

### Step-by-Step Solution:

1. **Understanding Root Pressure**: Root pressure is defined as the pressure created in the roots of plants due to osmotic action. It occurs when water is absorbed from the soil into the root cells, creating a pressure that pushes water upward through the xylem.

2. **Limitations of Root Pressure**: Although root pressure can contribute to the movement of sap (water and nutrients) from roots to the upper parts of the plant, it has limitations. It is not sufficient to explain the ascent of sap in all types of plants.

3. **Ascent of Sap**: The ascent of sap refers to the upward movement of water and dissolved minerals from the roots to the leaves and other parts of the plant. This process can occur even in plants that do not have roots or in conditions where root pressure is absent.

4. **Examples of Plants Without Root Pressure**: Certain plants, such as bryophytes (mosses), do not exhibit significant root pressure. Additionally, some trees can transport sap effectively even in seasons when root pressure is low or absent.

5. **Conclusion**: Therefore, root pressure cannot explain the ascent of sap in all plants and in all seasons. The correct answer to the question is that root pressure is unable to explain the ascent of sap because it is not found in "all plants in all seasons."

### Final Answer:
Root pressure is unable to explain the ascent of sap because it is not found in all plants in all seasons.

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