Clinostat is the apparatus used to

Options

A. Measure the rate of growth in plant
B. Measure the quantity of auxin in plant
C. Measure the effect of light on plant
D. Eliminate the effect of gravity or geotropism on plant.

Answer

To answer the question about the function of a clinostat, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Purpose of a Clinostat**:
- A clinostat is an apparatus specifically designed to study the effects of gravity on plant growth. It helps in understanding how plants respond to gravitational forces.

2. **Mechanism of Action**:
- The clinostat operates by rotating the plant samples. This rotation helps to eliminate the directional effects of gravity, allowing researchers to observe plant growth without the influence of gravitational pull.

3. **Applications of a Clinostat**:
- It is used to measure the rate of growth and development in plants. Additionally, it can be used to study the effects of microgravity, which is particularly useful in space research.

4. **Conclusion**:
- Based on its function and applications, the correct answer to the question is that a clinostat is used to eliminate the effect of gravity or geotropism on the plant.

### Final Answer:
**A clinostat is the apparatus used to eliminate the effect of gravity or geotropism on the plant.**

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