IB ESS Topic 2.1-2.3 Review

Front

What is a biomass pyramid?

Back

A biomass pyramid is a graphical representation that shows the total mass of living tissue at each trophic level in an ecosystem.

Front

What is assimilation in the nitrogen cycle?

Back

Assimilation is the process by which plant roots absorb ammonium ions and nitrate ions to create essential molecules like DNA, amino acids, and proteins.

Front

How do living organisms return carbon to the atmosphere?

Back

Living organisms return carbon to the atmosphere through decomposition and respiration.

Front

What is ammonification in the nitrogen cycle?

Back

Ammonification is the process where specialized soil bacteria consume leaf material and return nitrogen to the soil.

Front

What is net primary productivity?

Back

Net primary productivity is the organic material that remains after photosynthetic organisms have used some for their cellular energy needs.

Front

What is nitrogen fixation?

Back

Nitrogen fixation is the process of converting atmospheric nitrogen into a form that plants can absorb and use.

Front

What is nitrification?

Back

Nitrification is the process by which ammonium ions are converted into nitrites and then nitrates by bacteria.

Front

What is denitrification?

Back

Denitrification is the process by which nitrates are converted back into nitrogen gas, returning it to the atmosphere.

Front

What is gross primary productivity?

Back

Gross primary productivity is the total amount of organic material produced by photosynthetic organisms before any is used for respiration.

Front

What role do decomposers play in an ecosystem?

Back

Decomposers break down dead organic matter, returning nutrients to the soil and making them available for plants.