Decomposers and Cycles

Biogeochemical Cycles

Multiple Choice

Which of the following would be a good description of a population?

• A colony of ants

• The grass and ducks and fish at a pond

• The grass and ducks and fish and rocks and water in a pond

• An ant

Multiple Choice

Which of the following would be a good description of a ecosystem?

• A colony of ants

• The grass and ducks and fish at a pond

• The grass and ducks and fish and rocks and water in a pond

• An ant

Multiple Choice

Which of the following would be a good description of a community?

• A colony of ants

• The grass and ducks and fish at a pond

• The grass and ducks and fish and rocks and water in a pond

• An ant

Water Cycle

• Precipitation - when water falls from the sky

• Runoff - when water runs off the surface and ends up in lakes/ponds/rivers, etc.

• Seepage - when water seeps into the ground and becomes groundwater

• Evaporation - when water heats up and turns into a gas form

• Transpiration - when water evaporates from the plants of leaves

• Condensation - when water vapor cools down and turns into clouds

Multiple Choice

When warm, evaporated air rises, it cools and begins to turn into liquid again. This part of the water cycle is called:

• a: transpiration

• b: precipitation

• c: runoff

• d: condensation

Multiple Choice

Which term best describes a change of state from a liquid to a gas caused by the sun's energy?

• evaporation

• sublimation

• deposition

• precipitation

Multiple Choice

The process of plants losing water through their leaves is called ____.

• condensation

• evaporation

• transpiration

• exhaling

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

Nitrogen Cycle

• About 78% of the earth's atmosphere is nitrogen gas.

• 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 nitrifying bacteria change ammonium into nitrates, which is what plants can use

• Ammonification

• Denitrification

• Nitrification

• Nitrogen fixation

Multiple Choice

the process when nitrogen-fixing bacteria in the soil/on plant roots change nitrogen gas into ammonia

• Ammonification

• Denitrification

• Nitrification

• Nitrogen fixation

Multiple Choice

when denitrifying bacteria take the excess nitrates and turn it back into nitrogen gas

• 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.

Multiple Choice

There is no portion of the phosphorus cycle in the...

• atmosphere

• rocks

• water

• living organisms