Photosynthesis & The Carbon Cycle Review

Front

Which of the following does NOT produce carbon dioxide? Options: Photosynthesis, Burning Fossil Fuels, Animal Respiration, Plants Decaying

Back

Photosynthesis

Answer explanation

Photosynthesis is the process by which plants convert carbon dioxide and sunlight into glucose and oxygen, thus it does not produce carbon dioxide. In contrast, burning fossil fuels, animal respiration, and decaying plants all release carbon dioxide.

Front

Combustion is another word for __________.

Back

Burning

Answer explanation

Combustion refers to the chemical process of burning, where substances react with oxygen to release energy. Therefore, the correct answer is 'Burning', as it directly describes this process.

Front

Organisms that do not decompose can be buried and become what?

Back

fossil fuels

Answer explanation

Organisms that do not decompose can be buried under sediment over millions of years, transforming into fossil fuels like coal, oil, and natural gas, which are energy sources derived from ancient organic matter.

Front

Where can carbon be found?

Back

Atmosphere, soil, fossil fuels

Answer explanation

Carbon is present in various forms: in the atmosphere as carbon dioxide, in soil as organic matter, and in fossil fuels like coal and oil. Therefore, the correct answer is 'All of the above'.

Front

Which of the following processes removes carbon from the atmosphere? Combustion, Respiration, Photosynthesis, Death

Back

Photosynthesis

Answer explanation

Photosynthesis is the process by which plants absorb carbon dioxide from the atmosphere and convert it into glucose and oxygen, effectively removing carbon from the air. The other options do not remove carbon.

Front

What process occurs when coal (a fossil fuel) is used for energy?

Back

Combustion

Answer explanation

When coal is used for energy, it undergoes combustion, a chemical process where it reacts with oxygen to produce heat, light, carbon dioxide, and water. This is the primary method of energy generation from fossil fuels.

Front

Respiration is the process by which animals take in oxygen and release carbon dioxide.

Back

oxygen, carbon dioxide

Answer explanation

Respiration is the biological process where animals inhale oxygen and exhale carbon dioxide. This is essential for energy production in cells, making 'oxygen, carbon dioxide' the correct answer.

Front

The diagram shows the flow of organic molecules through an ecosystem. What two processes are identified by the labels X and Y?

Back

X: Decomposition
Y: Respiration

Answer explanation

In the ecosystem, X represents Decomposition, where organic matter is broken down, and Y represents Respiration, where organisms convert organic molecules into energy. This flow is essential for nutrient cycling.

Front

Which reason best explains the approximately 1°C increase in Earth's average surface temperature over the past century?

Back

Higher levels of carbon dioxide and other greenhouse gases in the atmosphere.

Answer explanation

The increase in Earth's average temperature is primarily due to higher levels of carbon dioxide and other greenhouse gases, which trap heat in the atmosphere, leading to global warming.

Front

Which process is primarily responsible for releasing oxygen into the atmosphere?

Back

Photosynthesis

Answer explanation

Photosynthesis is the process by which plants convert sunlight, carbon dioxide, and water into glucose and oxygen, releasing oxygen as a byproduct into the atmosphere, making it the primary source of atmospheric oxygen.