Atmosphere is very important for sustaining life because:

• It contains various gases like O₂, CO₂, N₂ which are required for various life processes by plants and animals.
• CO₂ gas is used by plants to prepare food . by the process called photosynthesis.
• Oxygen is required for combustion and respiration.
• Ozone layer acts as a protective layer which prevents harmful U.V. rays to enter the earth’s atmosphere.
• Atmosphere acts as a temperature buffer.