The essential role of air in the growth of green plants was revealed by

Options

A. Priestley
B. Van Niel
C. Blackmann
D. Emerson

Answer

To answer the question regarding the essential role of air in the growth of green plants, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Scientist**: The essential role of air in the growth of green plants was revealed by Joseph Priestley.

2. **Understand the Experiment**: In 1770, Priestley conducted a series of experiments to demonstrate the importance of air for plant growth.

3. **Describe the First Experiment**:
- Priestley lit a candle and placed it under a glass jar.
- The candle burned until the oxygen in the jar was depleted, at which point the flame extinguished.

4. **Describe the Second Experiment**:
- Priestley then placed a mouse inside a sealed jar.
- The mouse consumed the oxygen and eventually died due to lack of air.

5. **Combine the Elements in the Third Experiment**:
- In a crucial experiment, Priestley placed both a candle and a mouse in the same jar with a green plant.
- The plant produced oxygen through photosynthesis, which allowed the candle to burn and the mouse to survive.

6. **Conclusion**:
- Priestley concluded that plants play a vital role in replenishing the air with oxygen, which is essential for the survival of animals and the burning of candles.
- This experiment highlighted the importance of air (specifically oxygen and carbon dioxide) in the growth and survival of green plants.

### Final Answer:
The essential role of air in the growth of green plants was revealed by Joseph Priestley through his experiments in 1770.

---