What Two Processes Fuel the Carbon Cycle? — Reading Comprehension

The carbon cycle is the movement of carbon through Earth’s systems—air, water, land, and living things. Two key processes that fuel this cycle are photosynthesis and respiration. These processes help move carbon between the atmosphere and living organisms.

Photosynthesis happens in plants, algae, and some bacteria. 

These organisms take in carbon dioxide (CO₂) from the air and use sunlight to make food. During this process, carbon is stored in the plant’s tissues and becomes part of the food chain when animals eat the plants.

Respiration is how living things release energy from food. When animals and plants break down food for energy, they release carbon dioxide back into the atmosphere as a waste gas. This process happens in both plants and animals, even though plants also perform photosynthesis.

Together, photosynthesis and respiration create a balance. Plants remove carbon from the air, and animals (and plants) return it through respiration. This cycle keeps the amount of carbon in the atmosphere fairly steady over time.

These two natural processes are essential for life on Earth. They support food chains, help regulate climate, and keep ecosystems working properly.

Fun Fact: A forest can act like a “carbon sink,” storing more carbon during photosynthesis than it releases during respiration!

What are the two main processes that fuel the carbon cycle?

What gas do plants take in during photosynthesis?

What happens to carbon during photosynthesis?

What is released during respiration?

Why are photosynthesis and respiration important to the carbon cycle?

What happens when animals eat plants?

What is the main idea of the passage?

What would happen if photosynthesis stopped?