Earth's 4 Spheres
Nutrient Cycles
Photosynthesis or Cellular Respiration?
Sci Method
100

This sphere contains all the water on Earth, including oceans, lakes, and rivers.

What is the HYDROSPHERE?

100

This nutrient cycle involves nitrogen changing from the atmosphere into usable forms by plants.

What is the NITROGEN CYCLE?

100

This process uses sunlight to make glucose in plants.

What is PHOTOSYNTHESIS?

100

This is the first step in the scientific method where you ask a question about what you observe.

What is an OBSERVATION?

200

This sphere is made up of all living organisms on Earth.

What is the BIOSPHERE

200

An excessive amount of nutrients in a body of water (i.e., nitrogen or phosphorus).

What is EUTROPHICATION?

200

This molecule is the main product of photosynthesis and fuel for cellular respiration.

What is GLUCOSE?

200

This is an educated guess or prediction that can be tested.

What is a HYPOTHESIS?

300

This sphere includes the solid outer layer of Earth, such as rocks and soil.

What is the LITHOSPHERE?

300

The faster process of carbon moving through plants and animals 

What is FAST MOVING CARBON?

300

This process breaks down glucose to release energy for cells.

What is CELLULAR RESPIRATION?

300

In an experiment, this variable is changed by the scientist.

What is the INDEPENDENT VARIABLE?

400

This sphere is the layer of gases surrounding Earth.

What is the ATMOSPHERE?

400

The largest reservoir of carbon on the planet

What is the OCEAN?

400

The energy-carrying molecule produced in cellular respiration.

What is ATP?

400

This variable changes in response to the independent variable and is measured.

What is the DEPENDENT VARIABLE?

500

Interaction between these spheres can cause events like volcanic eruptions affecting the atmosphere and biosphere. Name any two of these Earth spheres.

What are the Lithosphere and Atmosphere (or Hydrosphere and Biosphere, etc.)?

500

This process converts nitrogen gas from the air into compounds plants can use.

What is NITROGEN FIXATION?

500

This gas is taken in by plants during photosynthesis and released by animals during cellular respiration.

What is CARBON DIOXIDE?

500

This type of experiment keeps all variables except one the same to test a hypothesis accurately.

What is a CONTROLLED EXPERIMENT?

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