Cylces of life

Cycles of life

Introduction to how water, carbon, nitrogen, and phosphorus are cycled through ecosystems.

Multiple Choice

What is it called when water changes from liquid to gas

• freezing

• evaportation

• condensation

Multiple Choice

How is water returned to earth?

• percolation

• precipitation

• evaporation

• transpiration

Carbon Cycle

Photosynthesis - how the carbon comes to earth from the atmosphere Cellular respiration - how the carbon is released from plants/animals back into the atmosphere Combustion - when carbon is released into the atmosphere by factories/cars Decomposition - when carbon is released atmosphere by dead plants/animals... some is turned into fossil fuels to be burnt later

Multiple Choice

What is the only way that carbon (CO2) goes from the atmosphere to living organisms?

• photosynthesis

• respiration

• decomposition

• combustion

Multiple Choice

What do plants do with carbon dioxide (CO2)

• Plants use CO2 to make carbohydrates.

• Plants use CO2 to produce extra sunshine.

Multiple Choice

What are two by products released by plants?

• water and carbon

• oxygen and water

• carbon and oxygen

• sugar and carbon

Nitrogen Cycle

Plants and animals must have nitrogen to make proteins and nucleic acids. However, the nitrogen gas is not usable by plants or animals - so the nitrogen cycle must happen to change nitrogen into a usable form through a series of steps. Most of this is done using bacteria & decomposers; however, some nitrogen enters the soil via lightning.

Nitrogen Cycle

Nitrogen fixation: the process when nitrogen-fixing bacteria in the soil/on plant roots change nitrogen gas into ammonia Ammonification: the process when decomposers break down dead stuff/animal wastes into ammonium Nitrification: the process when nitrifying bacteria change ammonium into nitrates, which is what plants can use Assimilation: when the plants take in the nitrates Denitrification: when denitrifying bacteria take the excess nitrates and turn it back into nitrogen gas

Multiple Choice

the process when decomposers break down dead stuff/animal wastes into ammonium

• Ammonification

• Denitrification

• Nitrification

• Nitrogen fixation

Multiple Choice

the process when decomposers break down dead stuff/animal wastes into ammonium

• Ammonification

• Denitrification

• Nitrification

• Nitrogen fixation

Phosphorus Cycle

This is the only cycle without an atmospheric portion. Phosphate is released via the weathering of rocks. Plants & some fungi take up phosphorus. Phosphorus moves from producers to consumers via the food web. Phosphorus is released back into the soil when organisms die & decomposers break them down. Phosphorus gets into water via runoff and leaching from the groundwater. Mining and agricultural runoff add to the phosphorus in the environment.