Mass flow of water occurs due to (A)_____ and (B)_____ properties of water.

Answer

To answer the question regarding the mass flow of water in plants, we need to identify the two properties of water that facilitate this process.

### Step-by-Step Solution:

1. **Understanding Mass Flow of Water**:
- Mass flow in plants refers to the movement of water through the plant's vascular system, particularly through the xylem. This movement is essential for transporting nutrients and maintaining turgor pressure.

2. **Identify the Properties of Water**:
- Water has unique properties that contribute to its movement in plants. The two key properties we need to focus on are:
- **Cohesion**: This is the property of water molecules to stick to each other. It allows water to form a continuous column in the xylem vessels, which is crucial for the upward movement of water.
- **Adhesion**: This is the property of water molecules to stick to other surfaces, such as the walls of the xylem vessels. This property helps water to climb up the walls of the xylem against the force of gravity.

3. **Role of Evaporation**:
- As water evaporates from the leaves (a process known as transpiration), it creates a negative pressure (tension) in the xylem. This tension pulls more water upward from the roots through the xylem.

4. **Conclusion**:
- Therefore, the mass flow of water occurs due to:
- (A) Cohesive properties of water
- (B) Adhesive properties of water

### Final Answer:
Mass flow of water occurs due to (A) Cohesive properties and (B) Adhesive properties of water.