Module 3 - Carbon Cycle Review

What is the main role of trees in the carbon cycle during the day while they are doing photosynthesis?

• They release carbon dioxide into the air.

• They take in CO₂ to make sugar.

• They break down sugars to produce energy.

• They absorb oxygen from the air.

Carbon can make up to (a)   chemical bonds.

• 4
• 5
• 6

Why is carbon so important in forming molecules?

• It can form millions of different molecules of different sizes and shapes

• It cannot form chains.

• It is not found in living things.

Explain how photosynthesis and cellular respiration work together to keep carbon moving and energy flowing in the environment.

• Photosynthesis and cellular respiration both release carbon dioxide.

• Photosynthesis takes in CO₂ and makes sugars while cellular respiration uses oxygen to break down sugars and releases CO₂.

• Both processes only occur at night.

• Photosynthesis and cellular respiration do not affect each other.

If a city plants more trees to help capture carbon, what effect might this have on the local carbon cycle?

• It would increase the amount of carbon dioxide in the air.

• It might help capture more carbon, keeping the cycle in balance.

• It would have no effect on the carbon cycle.

• It would decrease the amount of oxygen in the air.

As humans burn more fossil fuels, what will happen to the amount of carbon dioxide in the earth’s atmosphere?

• It will increase

• It will decrease

• It will stay the same

• It will disappear

Between 1960 and 2010, atmospheric CO₂ levels measured at an observatory in Hawaii changed in which of the following ways?

• Increased from about 320 ppm to about 390 ppm

• Decreased from about 390 ppm to about 320 ppm

• Stayed the same at about 350 ppm

• Fluctuated between 200 ppm and 400 ppm

Match!

• biosphere

• 
• geosphere

• 
• atmosphere

• 
• hydrosphere

• 

Match!

• CO₂

• Carbon dioxide

• H₂O

• Water

• C₆H₁₂O₆

• Nitrogen

• N

• Glucose

• C

• Carbon

What are the products of the photosynthesis reaction? What is made during photosynthesis?

• Sunlight and water

• Oxygen and glucose

• Carbon dioxide and water

• ATP and carbon