Grade 7 Cycles Quiz Flashcards
Animals use oxygen in the process of (blank) and make more CO2
Respiration
The (blank) is the main regulator of CO2 in the atmosphere because CO2 dissolve easily in it
Ocean
In the past huge deposits of carbon were stored as dead plants and animals (blank)
Decayed
Today these deposits are burned as fossil fuels which include (blank), (blank), and (blank)
natural gas, oil, and coal
More CO2 is released in the atmosphere today than in the past because of (blank)
Burning of fossil fuels
Another natural source of CO2 is (blank)
Volcanoes
Too much CO2 is responsible for the (blank) affect
Greenhouse
Write the equation for photosynthesis
CO2 plus H2O = sugar plus oxygen
Our atmosphere is (blank) nitrogen gas
78%
Animals and plants cannot directly use all the nitrogen found in our (blank)
Atmosphere
Only special bacteria can directly use nitrogen in our atmosphere and fix it so other organisms can benefit. These bacteria are called (blank) bacteria
Nitrogen fixing
Higher organisms use nitrogen to make their (blank)
Proteins
Animal waste decay by the action of bacteria which create (blank) and (blank) products rich in nitrogen and useful for plants to use again
Ammonia and nitrate
(Blank) bacteria in the soil can break down the ammonia into the gaseous form of nitrogen which is not available for use by plants and animals
Denitrificating
In another part of the cycle animals eat (blank) containing nitrogen which is again returned to the soil by (blank) or decaying (blank)and (blank)
In another part of the cycle animals eat plants which contain nitrogen which is again returned to the soil by animal waste and or decaying plants and animals
