Biodiversity Chapter 5 Section 1

Main Idea Biodiversity maintains a healthy biosphere and provides direct and indirect value to humans.

What are three types of biodiversity? Why is biodiversity important? Thinking Questions What are three types of biodiversity? Why is biodiversity important? What are the direct and indirect values of biodiversity? Copyright © McGraw-Hill Education

Review Vocabulary Gene -functional unit that controls the expression of inherited traits and is passed from generation to generation

Extinction occurs when the last member of a species dies. What is biodiversity? Biodiversity is the variety of life in an area that is determined by the number of different species in that area. Biodiversity increases the stability of an ecosystem and contributes to the health of the biosphere. Extinction occurs when the last member of a species dies. There are 3 main types of biodiversity: genetic, species, and ecosystem.

What is biodiversity? Genetic diversity Genetic diversity is the variety of genes or inheritable characteristics that are present in a population. Genetic diversity increases the chances that some species will survive during changing environmental conditions (camouflage) or during the outbreak of disease.

Species diversity The number of different species and the relative abundance of each species in a biological community is called species diversity. As you move geographically from polar regions to the equator, species diversity increases What is biodiversity?

What is biodiversity? Ecosystem diversity The variety of ecosystems that are present in the biosphere is called ecosystem diversity. An ecosystem is made up of interacting populations and the abiotic factors that support them.

The Importance of Biodiversity Direct economic value Humans depend on plants and animals for food, clothing, energy, and medicine. Most of the world’s food crops come from just a few species. Wild species serve as reservoirs of desirable genetic traits that might be needed to improve commercial crop species. Scientists continue to find new extracts from plants and other organisms that help in the treatment of human diseases.

Indirect economic value The Importance of Biodiversity Indirect economic value A healthy biosphere provides many services to humans: Green plants provide oxygen and remove carbon dioxide. Natural processes provide drinking water that is safe for human use. It is often difficult to assign an economic value to biosphere services.

Aesthetic and scientific values The Importance of Biodiversity Aesthetic and scientific values There is value in maintaining healthy ecosystems that are beautiful or interesting to study It is difficult to assign economic value to these services.

What are three types of biodiversity? Why is biodiversity important? Thinking Questions What are three types of biodiversity? Why is biodiversity important? What are the direct and indirect values of biodiversity? Copyright © McGraw-Hill Education