The Carbon and Oxygen Cycle

Dr. Forrester introduces carbon, an essential element in nature, explaining its presence in organic compounds and its role in the carbon cycle. The video covers photosynthesis, where plants use carbon dioxide and sunlight to create food, and respiration, where animals release carbon dioxide back into the ecosystem. It also discusses the impact of fossil fuels and combustion on carbon levels. The oxygen cycle is explained, highlighting how plants and animals exchange oxygen and carbon dioxide, maintaining balance in the ecosystem.

What is the primary role of carbon dioxide in the atmosphere?

• To create oxygen for plants

• To provide energy for animals

• To trap heat and maintain Earth's temperature

• To act as a food source for humans

During photosynthesis, what do plants produce using carbon dioxide and water?

• Carbohydrates

• Proteins

• Fats

• Minerals

How is carbon dioxide released back into the ecosystem during respiration?

• Through decomposition

• Through photosynthesis

• By exhaling

• By absorbing sunlight

What is the byproduct of photosynthesis that is crucial for animal life?

• Hydrogen

• Oxygen

• Nitrogen

• Carbon dioxide

In the oxygen cycle, what role do plants play?

• They produce oxygen and consume carbon dioxide

• They convert oxygen into nitrogen

• They consume oxygen and release carbon dioxide

• They store oxygen for future use