What is the significance of the ozone layer?

The significance of the ozone layer primarily lies in its role in protecting Earth from harmful ultraviolet (UV) radiation emitted by the sun. The ozone layer is located in the stratosphere and consists of ozone (O3) molecules that absorb the majority of the sun's harmful UV rays. This absorption is crucial because excessive exposure to UV radiation can lead to various harmful effects, including an increase in skin cancer and cataracts, as well as negative impacts on ecosystems and wildlife.

In contrast, the other options do not accurately represent the role of the ozone layer. For instance, while it is true that carbon dioxide is a greenhouse gas that contributes to the greenhouse effect, the ozone layer does not absorb it. Similarly, photosynthesis is primarily facilitated by chlorophyll in plants, which absorbs sunlight, but the ozone layer does not directly contribute to this process. Lastly, while the ozone layer does play a role in the overall regulation of temperature through its interactions with sunlight, its paramount function is the protection from UV radiation.