Question 23

The ozone layer is a region of the stratosphere.

The ozone layer is primarily located within the stratosphere, which is the second layer of Earth's atmosphere. This region contains a high concentration of ozone (O3) molecules, which absorb the majority of the sun's harmful ultraviolet radiation.

A) The stratosphere

This option is correct because the ozone layer is situated within the stratosphere, approximately 10 to 30 miles above the Earth's surface. The stratosphere is characterized by a temperature increase with altitude due to the absorption of UV radiation by ozone, making it essential for protecting life on Earth.

B) The mesosphere

The mesosphere is incorrect as it is the third layer of the atmosphere, located above the stratosphere. While it plays a role in atmospheric processes, it does not contain the ozone layer, which is specifically found in the stratosphere.

C) The thermosphere

This option is also incorrect because the thermosphere is the fourth layer of the atmosphere, situated above the mesosphere. Although it contains ionized gases and is where the auroras occur, it does not house the ozone layer.

D) The exosphere

The exosphere is incorrect as it is the outermost layer of the Earth's atmosphere, extending out into space. It is primarily composed of extremely thin air and does not contain the ozone layer, which is confined to the lower atmospheric layers.

Conclusion

In conclusion, the correct answer is A) The stratosphere, as it is the specific atmospheric layer that contains the ozone layer. The other options fail to provide the right context regarding the location of the ozone layer, which is crucial for filtering harmful UV radiation from the sun. Understanding the atmospheric layers is essential for comprehending the protective role of the ozone layer in maintaining life on Earth.