What is the role of ozone layer in atmosphere?

Answer

### Step-by-Step Solution:

1. **Understanding the Composition of the Ozone Layer**:
- The ozone layer is primarily composed of ozone (O3) molecules. These molecules are formed when oxygen (O2) interacts with ultraviolet (UV) radiation from the sun.

2. **Function of the Ozone Layer**:
- The primary role of the ozone layer is to absorb the majority of the sun's harmful ultraviolet (UV) radiation. This radiation can cause various health issues, including skin cancer and cataracts, and can also have detrimental effects on the environment.

3. **Protection Against UV Rays**:
- By absorbing UV radiation, the ozone layer prevents these rays from reaching the Earth's surface. This protective function is crucial for maintaining the health of living organisms and the stability of ecosystems.

4. **Formation of Oxygen and Free Radicals**:
- When UV radiation interacts with ozone (O3), it can break down the ozone molecules, resulting in the formation of oxygen gas (O2) and free radicals. While free radicals can be reactive, the process of ozone absorbing UV radiation is vital for protecting life on Earth.

5. **Conclusion**:
- In summary, the ozone layer acts as a shield for the Earth, absorbing harmful UV radiation and thereby protecting human health and the environment.