Select an incorrect statement about mobilisation of minerals /food in plants

Options

A. buds need energy for growth and development of the photosynthetic apparatus
B. xylem movement can be upwards or downwards
C. the source-sink relationship is variable
D. direction of movement in the phloem can be upwards

Answer

To solve the question of selecting an incorrect statement about the mobilization of minerals/food in plants, we will analyze each statement provided.

### Step-by-Step Solution:

1. **Understanding the Question**: The task is to identify which of the given statements about the mobilization of minerals or food in plants is incorrect.

2. **Analyzing the Statements**:
- **Statement 1**: "Buds need energy for growth and development of the photosynthetic apparatus."
- **Analysis**: This statement is correct. Buds do require energy for their growth and development, which includes the development of the photosynthetic apparatus.

- **Statement 2**: "Movement through xylem is unidirectional."
- **Analysis**: This statement is also correct. Xylem transports water and minerals from the roots to the leaves in a unidirectional manner (upward).

- **Statement 3**: "The source-sink relationship is variable."
- **Analysis**: This statement is correct. In plants, the source (photosynthetic parts) and sink (non-photosynthetic parts) relationship can change based on the plant's needs and the season.

- **Statement 4**: "Direction of movement in the phloem can be upward."
- **Analysis**: This statement is misleading. While phloem can transport food in both directions (upward and downward), the phrasing suggests that it can only move upward, which is incorrect. The movement in phloem is indeed bidirectional, but the statement as presented can be interpreted as incorrect.

3. **Identifying the Incorrect Statement**: Based on the analysis, the second statement regarding the direction of movement in the phloem is misleading, as it implies a limitation that does not exist.

4. **Conclusion**: The incorrect statement about the mobilization of minerals/food in plants is the one suggesting that the direction of movement in the phloem can only be upward.

### Final Answer:
The incorrect statement is: "Direction of movement in the phloem can be upward."