1.2. The Carbon Cycle

• The carbon cycle involves natural and human-influenced processes
• The carbon cycle includes exchanges between the atmosphere, land, oceans, and living organisms.


  True
• Decomposition releases CO₂ back into the atmosphere and soil.

  True
• Order the key processes within the carbon cycle:

  1️⃣ Photosynthesis

  2️⃣ Respiration

  3️⃣ Decomposition

  4️⃣ Combustion
• What is the carbon cycle?

  Exchange of carbon atoms
• Match the process with its description:

  Photosynthesis ↔️ Plants absorb CO₂ and convert it into glucose

  Respiration ↔️ Plants and animals release CO₂

  Decomposition ↔️ Decomposers break down organic matter

  Combustion ↔️ Burning fossil fuels releases CO₂
• Combustion releases CO₂ into the atmosphere
• Human activities have disrupted the equilibrium of the carbon cycle.

  True
• Burning fossil fuels releases large amounts of CO₂ into the atmosphere
• What are the three main reservoirs involved in the carbon cycle?

  Atmosphere, land, oceans
• Arrange the following carbon cycle processes in a logical sequence of carbon transfer:

  1️⃣ Photosynthesis

  2️⃣ Respiration

  3️⃣ Decomposition

  4️⃣ Combustion

  5️⃣ Ocean Exchange
• Oceans act as natural carbon sinks by absorbing CO₂ through dissolution and biological processes
• Artificial carbon sinks, such as underground storage, require suitable geological formations
• Ocean exchange is a process where CO₂ dissolves from the atmosphere into the oceans and vice versa.


  True
• What is released from volcanoes through eruptions?

  CO₂
• What is the main source of carbon absorbed by plants during photosynthesis?

  Atmospheric CO₂
• What human activities have disrupted the carbon cycle's equilibrium?

  Fossil fuel combustion and deforestation
• Match the carbon sink with its benefit:

  Oceans ↔️ Reduces atmospheric CO₂ and buffers acidity.

  Forests ↔️ Stores carbon in biomass and supports biodiversity.

  Soils ↔️ Enhances fertility and reduces CO₂.
• Carbon sinks help to mitigate the effects of climate change
• Steps to address disruptions in the carbon cycle:

  1️⃣ Reduce fossil fuel combustion

  2️⃣ Increase reforestation efforts

  3️⃣ Develop carbon capture technologies

  4️⃣ Promote sustainable land use practices
• What happens to the ocean's ability to absorb CO₂ when it becomes acidified?

  Decreases
• What releases CO₂ back into the atmosphere as organic matter is broken down?

  Decomposition
• The carbon cycle involves processes that transfer carbon between the atmosphere, land, and oceans
• Which process releases CO₂ back into the atmosphere as plants and animals break down glucose for energy?

  Respiration
• What is the primary role of carbon sinks in the carbon cycle?

  Absorb and store CO₂
• Match the natural carbon sink with its key reservoir:

  Oceans ↔️ Absorb CO₂

  Forests ↔️ Store carbon in biomass

  Soils ↔️ Store carbon from organic matter
• Cement production releases CO₂ from limestone, contributing to atmospheric CO₂ levels.


  True
• What molecule is absorbed by plants during photosynthesis?

  CO₂
• Burning fossil fuels for energy is an anthropogenic source of CO₂
• Cement production releases CO₂ from heating limestone
• Match the carbon cycle process with its description:

  Photosynthesis ↔️ Plants absorb CO₂ and store carbon.

  Respiration ↔️ Plants and animals release CO₂.

  Decomposition ↔️ Decomposers break down organic matter.

  Combustion ↔️ Burning fossil fuels releases CO₂.
• What are three natural carbon sinks mentioned in the study material?

  Oceans, forests, and soils
• Deforestation reduces the ability of forests to store carbon.


  True
• What is the main human-induced disruption to the carbon cycle?

  Imbalance in carbon exchange
• Increased atmospheric CO₂ enhances the greenhouse effect and global warming.

  True
• What do plants and animals release during respiration?

  CO₂
• Which reservoirs are involved in ocean exchange within the carbon cycle?

  Atmosphere and Oceans
• Plants absorb CO₂ from the atmosphere during photosynthesis
• What do plants store carbon in during photosynthesis?

  Biomass
• In photosynthesis, plants absorb CO₂ from the atmosphere and convert it into glucose