Exploring Biogeochemical Cycles

What does the law of conservation of mass state?

• Mass can be destroyed but not created.

• Mass can be created but not destroyed.

• Mass can be neither created nor destroyed, only rearranged.

• Mass can be created and destroyed.

Which process involves water transforming from liquid to vapor?

• Percolation

• Precipitation

• Evaporation

• Condensation

What is transpiration?

• Evaporation of water from plants

• Evaporation of water from oceans

• Condensation of water vapor

• Precipitation of water droplets

How does carbon return to the atmosphere through respiration?

• By breaking down food using oxygen and releasing CO2

• By erosion of marine organisms

• By photosynthesis in plants

• By combustion of fossil fuels

What is the role of bacteria in the nitrogen cycle?

• They decompose organic matter into carbon.

• They convert nitrates into ammonia.

• They release nitrogen gas back into the atmosphere.

• They fix nitrogen from the atmosphere into usable compounds.

What is nitrogen fixation?

• Absorption of nitrogen by plants

• Production of ammonia from nitrogen in the atmosphere

• Conversion of nitrates to nitrogen gas

• Decomposition of organic matter

Which process converts ammonia into nitrates and nitrites?

• Nitrogen fixation

• Ammonification

• Denitrification

• Nitrification

Where is phosphorus commonly found?

• In the atmosphere

• In living organisms

• In rocks and minerals

• In fossil fuels

What is the limiting nutrient in an ecosystem?

• A nutrient that is abundant and cycles quickly

• A nutrient that is scarce or cycles very slowly

• A nutrient that is not used by plants

• A nutrient that is only found in the atmosphere

Why are fertilizers important for crops?

• They prevent the growth of algae.

• They reduce the need for water.

• They increase the acidity of the soil.

• They contain nutrients that may be scarce in the soil.