Question

Name the regions of the atmosphere where oxygen and ozone play key roles respectively-

• A. mesosphere , startospherer
• B. troposphere, stratosphere
• C. ionosphere , exosphere
• D. ozonesphere , thermosphere

Answer 1

Answer: (B)

Oxygen plays a key role in the troposphere whereas ozone in the stratosphere.

Role of oxygen in the troposphere

• Oxygen is a chemical element with an atomic number of 8
• Oxygen forms a chemical compound $\left(O_2\right)$ of two oxygen atoms which is a colorless gas at normal temperatures and pressures.​
• Oxygen plays a critical role in respiration, the energy-producing chemistry that drives the metabolisms of most living things
• The troposphere is the lowest layer of Earth's atmosphere, where oxygen can be found in 21%. this layer has the highest amount of oxygen.
• All biological activity takes place in the troposphere for which oxygen is required.
• Humans, along with many other creatures, need oxygen in the air we breathe to stay alive. Oxygen is generated during photosynthesis by plants and many types of microbes. Plants both use oxygen (during respiration) and produce it (via photosynthesis)

Role of ozone in the stratosphere

• ​Ozone $\left(O_3\right)$ is a highly reactive gas composed of three oxygen atoms.
• The stratosphere is the second layer of Earth's atmosphere.
• The ozone layer in the stratosphere absorbs a portion of the radiation from the sun, preventing it from reaching the planet's surface.
• Most importantly, it absorbs the portion of UV(ultraviolet) light called UVB.
• UVB is a kind of ultraviolet light from the sun (and sun lamps) that has several harmful effects.