Which of the following processes does not add CO₂ to the atmosphere?

The correct answer is Photosynthesis.

Key Points

• Photosynthesis is the process by which green plants, algae, and some bacteria convert light energy into chemical energy.
• During photosynthesis, plants absorb carbon dioxide (CO₂) from the atmosphere and release oxygen (O₂) as a byproduct.
• This process occurs primarily in the chloroplasts of plant cells, which contain the pigment chlorophyll.
• Photosynthesis is essential for the removal of CO₂ from the atmosphere, helping to regulate atmospheric CO₂ levels.
• The overall chemical equation for photosynthesis is: 6CO₂ + 6H₂O + light energy → C₆H₁₂O₆ + 6O₂.

Additional Information

• Volcanic Eruptions: These events release significant amounts of CO₂ and other gases into the atmosphere from the Earth's crust.
• Organic Matter Decay: Decomposition of organic matter by microorganisms releases CO₂ as a byproduct of respiration.
• Respiration: Both plants and animals respire, consuming oxygen and releasing CO₂ as a result of metabolic processes.
• Combustion: Burning of fossil fuels and biomass releases stored carbon in the form of CO₂ into the atmosphere.
• In contrast, photosynthesis is a carbon sink process, meaning it absorbs CO₂ rather than emitting it, thus playing a critical role in reducing atmospheric CO₂ levels.