Which would do maximum harm to tree

Options

A. Loss of half of its branches
B. Loss of all of its leaves
C. Loss of all its bark
D. Loss of half of its leaves

Answer

To determine which option would do the maximum harm to a tree, we need to analyze the consequences of losing each part of the tree mentioned in the question: branches, leaves, and bark.

### Step-by-Step Solution:

1. **Understanding the Functions of Tree Parts**:
- **Bark**: The bark is the outer layer of the tree trunk. Its primary function is to protect the tree and facilitate a limited exchange of gases through lenticels. While important, the loss of bark does not immediately threaten the tree’s survival.
- **Branches**: Branches support the leaves and help in the structural integrity of the tree. However, losing half of the branches may affect the tree’s ability to capture sunlight but does not critically endanger its survival.
- **Leaves**: Leaves are crucial for photosynthesis, where the tree synthesizes food (glucose). They also play a significant role in transpiration, which helps in water movement throughout the plant, and in gaseous exchange, allowing the tree to breathe.

2. **Analyzing the Options**:
- **Loss of Half of Its Branches**: This would reduce the tree's ability to photosynthesize but would not be fatal.
- **Loss of All of Its Leaves**: This would critically impair the tree's ability to produce food, carry out respiration, and maintain water movement. Without leaves, the tree would not survive for long.
- **Loss of All of Its Bark**: While this would expose the inner tissues to damage, the tree could still survive for a while without bark, as long as the vascular tissues remain intact.
- **Loss of Half of Its Leaves**: This would reduce photosynthesis and transpiration but would not be as detrimental as losing all leaves.

3. **Conclusion**:
- Based on the analysis, the **loss of all of its leaves** would do the maximum harm to the tree. Without leaves, the tree cannot perform photosynthesis, leading to a lack of energy and ultimately death.

### Final Answer:
The option that would do maximum harm to the tree is the **loss of all of its leaves**.