Snow, sleet, rain and hail are all forms of

• condensation
• evaporation
• precipitation
• transpiration

Most of our air is Nitrogen and is not useable. This form of Nitrogen is called

• nitrogen fixation
• nitrogen cycle
• nitrous oxide
• free nitrogen

___________ are responsible for Nitrogen fixation in our atmosphere.

• Bacteria
• Decomposers
• Lightening
• All of the above

Complete the cycle for number 1

• carbon dioxide
• glucose
• oxygen
• glucose and oxygen

Complete the cycle for number 2

• carbon dioxide
• glucose
• oxygen
• glucose and oxygen

Which of the following is responsible for releasing carbon into the atmosphere?

• animals, plants, bacteria, factories
• animals, factories, cars, burning wood
• plants, cutting down trees, decaying animals
• burning wood, bicycles, animal feces

How does the concentration of carbon dioxide in the atmosphere affect climate?

• As carbon concentration increases, temperatures decrease.
• As carbon concentration decreases, temperatures increase.
• As carbon concentration increases, temperatures increase.
• Carbon dioxide concentrations have no effect on climate.

How do living things return carbon into the atmosphere and oceans?

• combustion
• decay
• photosynthesis
• respiration

Where is carbon stored in the planet?

• in rocks, atmosphere, soil, sediments, fossil fuels, the oceans and in living things
• in plants and algae only
• it is not stored
• only in the atmosphere

Legumes host nitrogen fixing bacteria, and thus are good crops to plant to replenish the soil.

• true
• false