Earth's cycles

Certain stages of the water cycle are most likely occurring under certain weather conditions.  Which stage is most likely going to occur on a warm, sunny day?

• precipitation
• condensation
• evaporation

How does the amount of water circulating in the water cycle change?

• The amount of water remains constant
• The amount of water increases each time it rains
• he amount of water decreases and then increases each day
• The amount of water decreases every time evaporation occurs

What converts nitrogen gas into a usable form for plants and animals?

• bacteria

• rain

• fungi

• car exhaust

Organisms that need nitrogen to survive.

• only plants

• only animals

• only bacteria

• all living things

How is nitrogen "fixed" into a usable form for plants?

• Through action of bacteria only

• Through lightning only

• Through action of bacteria and lightning

• Through photosynthesis

How do animals get the nitrogen they need?

• From the air they breathe

• From the water they drink

• From the food they eat

• From the sun

Gas that makes up 78% of our atmosphere.

• Oxygen

• Nitrogen

• Hydrogen

• Carbon Dioxide

Phosphorous is passed from plants to ____ who eat them

• plants
• animals
• scavengers

_____ carries phosphorous from the soil into our waterways. .

• precipitation

• runoff

• transpiration

• condensation

What role do decomposers play in the phosphorous cycle?

• absorb phosphorous 
• release phosphorous into atmosphere
• return phosphorous into the soil
• combustion