Oxygen Cycle
This process in plants produces oxygen using sunlight.
What is photosynthesis
This gas in the atmosphere contains carbon and is used by plants.
What is carbon dioxide
This simple sugar made by plants stores carbon and energy.
What is glucose
Most of Earth’s nitrogen is found in this part of the planet.
What is the atmosphere
This industrial process makes ammonia from nitrogen gas for fertilizers.
What is the Haber-Bosch process
This process uses oxygen to release energy from food.
What is cellular respiration
This process removes carbon dioxide from the atmosphere.
What is photosynthesis
This fossil fuel forms from ancient plant remains buried underground.
What is coal
This process changes nitrogen gas into ammonia that plants can use.
What is nitrogen fixation
Farmers add this to soil to increase plant growth.
What is fertilizer
Most oxygen on Earth is found bonded in this part of the planet.
What is Earth’s crust
This process releases carbon dioxide back into the air when organisms break down food.
What is cellular respiration
This sedimentary rock made of calcium carbonate stores carbon for long periods of time.
What is limestone
Plants absorb nitrogen from the soil mainly in this form.
What are nitrates
This environmental problem happens when fertilizer runoff causes heavy algae growth in water.
What is eutrophication
Animals need this gas to carry out cellular respiration
What is oxygen
This energy source from space drives photosynthesis and the carbon cycle.
What is the Sun
The oceans store carbon in this dissolved gas form.
What is dissolved carbon dioxide
This process returns nitrogen gas back to the atmosphere.
What is denitrification
These bacteria live in the roots of legumes and help fix nitrogen.
What are nitrogen fixing bacteria
This form of oxygen high in the atmosphere helps protect Earth from ultraviolet radiation.
What is ozone
This human activity adds large amounts of carbon dioxide to the atmosphere.
What is burning fossil fuels
Living plants and animals store carbon in this general form.
What is organic matter
These microorganisms carry out many steps of the nitrogen cycle in the soil.
What are bacteria
Human fertilizer use has increased the amount of usable nitrogen in this global cycle.
What is the nitrogen cycle