Unit 3 Review

Increase in human population impacts which of the spheres?

• biosphere

• biosphere and hydrosphere

• biosphere, hydrosphere, atmosphere

• biosphere, hydrosphere, atmosphere, geosphere

Combustion occurs in the _____ Cycle.

• Water

• Carbon

• Oxygen

• Nitrogen

Through which process do living organisms RELEASE carbon dioxide (CO2) into the atmosphere

• photosynthesis

• Cellular Respiration

• transpiration

• combusion

How does carbon dioxide in the atmosphere enter into living organisms?

• burning of trees

• combustion of fossil fuels

• photosynthesis

• transpiration

How do living things contribute to the water cycle?

• precipitation

• condensation

• evaporation

• transpiration

Which nutrient cycle needs to be fixed before most living organisms can use it?

• Nitrogen

• Oxygen

• Carbon

• Water

What is the greenhouse effect?

• Gases are trapped in Earth's atmosphere and cool the planet

• Gases are trapped in Earth's atmosphere and warm the planet

• The sun is heating the planet at a higher rate

• The sun and moon are pulling heat toward the surface of the Earth

In an ecosystem, bacteria that inhabit the roots of certain plants and soil play an essential role in cycling what nutrient?

• Oxygen

• Water

• Carbon

• Nitrogen

What Gas makes up 20% of Earth's Atmosphere?

• Water Vapor

• Oxygen

• Carbon

• Nitrogen

What protects the Earth from the Sun's Ultraviolet (UV) radiation

• Space between the Sun and Earth

• water vapor in the tropsophere

• The ozone layer

• the asteroid belt