1.1.1 The Earth's Atmosphere

• Nitrogen makes up approximately 78% of the Earth's atmosphere.


  True
• What percentage of the Earth's atmosphere is argon?

  0.9%
• Order the layers of the Earth's atmosphere from lowest to highest altitude.

  1️⃣ Troposphere

  2️⃣ Stratosphere

  3️⃣ Mesosphere

  4️⃣ Thermosphere

  5️⃣ Exosphere
• The ozone layer, which absorbs UV radiation, is located in the stratosphere.
• Which atmospheric layer absorbs high-energy solar radiation?

  Thermosphere
• What is the key feature of the troposphere that supports life?

  Weather systems
• The coldest layer of the atmosphere is the mesosphere.
• The exosphere's thin gas layer merges with space.


  True
• Which atmospheric gas is required for respiration in animals and plants?

  Oxygen
• What role does carbon dioxide play in the Earth's atmosphere?

  Regulates temperature
• Which atmospheric layer contains the ozone layer?

  Stratosphere
• Where are most of the Earth's weather systems located?

  Troposphere
• The Earth's atmosphere is held in place by the Earth's gravity
• Oxygen constitutes about 21% of the Earth's atmosphere.
• Carbon dioxide makes up approximately 0.04% of the Earth's atmosphere.


  True
• Which atmospheric layer contains weather systems and most water vapor?

  Troposphere
• The mesosphere protects Earth from meteoroids by burning them up.


  True
• The outermost layer of the atmosphere that merges with space is called the exosphere.
• The stratosphere's ozone layer absorbs harmful UV radiation.


  True
• What phenomenon occurs in the thermosphere due to ionization?

  Auroras
• Match each atmospheric gas with its significance:

  Nitrogen (N₂) ↔️ Essential for plant growth

  Oxygen (O₂) ↔️ Required for respiration

  Argon (Ar) ↔️ Inert gas in industry

  Carbon Dioxide (CO₂) ↔️ Regulates temperature
• Nitrogen fixation in the atmosphere is essential for plant growth.
• Argon is an inert gas used in industrial applications.


  True
• The ozone layer absorbs harmful UV radiation from the Sun.
• Carbon dioxide is a key greenhouse gas that traps heat in the atmosphere.


  True
• Photosynthesis releases oxygen into the atmosphere.