Approximately How Many Species Have We Described Out of the Species

question 21

Multiple Choice

Approximately how many species have we described out of the species alive today?

• A)We have described almost all of the species on Earth.
• B)We have described about one-eighth of the species on Earth.
• C)We have described about one-quarter of the species on Earth.
• D)We have described about half of the species on Earth.
• E)We have described only a small fraction of the species on Earth.

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Definitions:

Natural Resources

Materials or substances that occur in nature and can be used for economic gain, such as minerals, forests, water, and fertile land.

Birthrate

The number of live births per 1,000 people in a population over a specified period, often used as an indicator of demographic trends.

U.S. History

The study of the history of the United States of America from its founding to the present day, focusing on major events, figures, and social changes over time.

Demographic Transition Model

The Demographic Transition Model is a theoretical model that describes the transition from high birth and death rates to low birth and death rates as a country develops from a pre-industrial to an industrialized economic system.