It is a common observation that the roots of plants always grow downwards, while the shoots of plants always grow upwards. Which type of growth movement is responsible for the given observation?

Options

A. Geotropism
B. Phototropism
C. Hydrotropism
D. Chemotropism

Answer

### Step-by-Step Solution:

1. **Understanding Plant Growth Directions**:
- Plants exhibit two main types of growth movements: the roots grow downwards and the shoots grow upwards. This directional growth is crucial for their survival and functioning.

2. **Identifying the Type of Growth Movement**:
- The growth movement of roots towards the gravitational pull (downwards) is known as positive geotropism (or gravitropism). This means that the roots are positively responding to gravity.

3. **Identifying the Growth Movement of Shoots**:
- Conversely, the growth movement of shoots away from the gravitational pull (upwards) is known as negative geotropism. This indicates that the shoots are negatively responding to gravity.

4. **Functionality of Growth Directions**:
- Roots grow downwards to anchor the plant and absorb water and minerals from the soil. Shoots grow upwards to access sunlight for photosynthesis, which is essential for the plant's energy production.

5. **Conclusion**:
- Therefore, the type of growth movement responsible for the roots growing downwards is positive geotropism, while the shoots growing upwards is due to negative geotropism.