Carbon cycle

Front

When humans burn fossil fuels, most of the carbon quickly enters the                       as carbon dioxide. Options: Water, Atmosphere, Sun, Air

Back

Atmosphere

Front

How do living organisms return carbon to the atmosphere in the carbon cycle?

Back

decomposition and respiration

Front

In the carbon cycle, producers take in the gas __

Back

carbon dioxide

Front

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

Back

Photosynthesis

Front

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

Back

fossil fuels

Front

If the plant population decreased, the amount of carbon would _________. Options: Stay the same, Increase, Decrease

Back

Increase

Front

Which of the following creates a calcium carbonate structure?
Options: plants, cows, corals, decomposers

Back

corals

Front

The average temperature of the surface of Earth has increased approximately 1°C in the past century. Which reason best explains this increase in temperature? Options: lower levels of ozone in the atmosphere, lower levels of nitrogen in the atmosphere, higher levels of carbon dioxide and other greenhouse gases in the atmosphere, higher levels of oxygen in the atmosphere

Back

higher levels of carbon dioxide and other greenhouse gases in the atmosphere

Front

Why is the ocean important to the carbon cycle?

Back

It keeps sediment containing carbon underwater for millions of years.

Front

What is happening at 1? Options: respiration: releasing CO₂, decomposing CO₂ in the soil, photosynthesis: absorbing CO₂, turning CO₂ from the atmosphere into organic molecules

Back

respiration: releasing CO₂