Section 16.4 Threats to Biodiversity. KEY CONCEPT The impact of a growing human population threatens biodiversity.

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1 Section 16.4 Threats to Biodiversity KEY CONCEPT The impact of a growing human population threatens biodiversity.

2 Preserving biodiversity is important to the future of the biosphere. The loss of biodiversity has long-term effects. loss of medical and technological advances extinction of species loss of ecosystem stability

3 Loss of habitat eliminates species. Habitat fragmentation prevents an organism from accessing its entire home range. occurs when a barrier forms within the habitat often caused by human development

4 Loss of habitat eliminates species. Habitat corridors are a solution to the problem. corridors can be road overpasses or underpasses allow species to move between different areas of habitat

5 Introduced species can disrupt stable relationships in an ecosystem. An introduced species is one that is brought to an ecosystem by humans. accidental purposeful Invasive species can have an environmental and economic impact.

6 Introduced species can disrupt stable relationships in an ecosystem. Invasive species often push out native species. Burmese python (Florida Everglades)

7 Introduced species can disrupt stable relationships in an ecosystem. Invasive species often push out native species. mice (Australia)

8 Introduced species can disrupt stable relationships in an ecosystem. Invasive species often push out native species. kudzu (southeastern United States)

9 Section 19.1 Diversity of Protists KEY CONCEPT Kingdom Protista is the most diverse of all the kingdoms.

10 Protists can be animal-like, plantlike, or fungus-like. Protists are eukaryotes that are not animals, plants, or fungi.

11 Protists can be animal-like, plantlike, or fungus-like. Animal-like protists consume other organisms. heterotrophs single-celled

12 Protists can be animal-like, plantlike, or fungus-like. An amoeba is an animal-like protist that feeds by engulfing food.

13 Protists can be animal-like, plantlike, or fungus-like. A paramecium is an animal-like protist that has no cell wall.

14 Protists can be animal-like, plantlike, or fungus-like. Plant-like protists are photosynthetic. single-celled, colonial, or multicellular no roots, stems, or leaves

15 Protists can be animal-like, plantlike, or fungus-like. A euglena has both animal-like structures such as an eyespot, contractile vacuoles, and flagella and plantlike structures, such as chloroplasts.

16 Protists can be animal-like, plantlike, or fungus-like. Fungus-like protists decompose dead organisms. heterotrophs can move, whereas fungi cannot

17 Protists can be animal-like, plantlike, or fungus-like. A slime-mold is a fungus-like protist.

18 Protists are difficult to classify. Protista is one kingdom in the domain Eukarya.

19 Protists are difficult to classify. Protist classification will likely change. Some protists are not closely related. Molecular evidence supports reclassification.

20 Section 19.6 Ecology of Fungi KEY CONCEPT Fungi recycle nutrients in the environment.

21 Fungi may be decomposers, pathogens, or mutualists. Fungi and bacteria are the main decomposers in any ecosystem. decompose dead leaves, twigs, logs, and animals return nutrients to the soil can damage fruit trees and wooden structures

22 Fungi may be decomposers, pathogens, or mutualists. Fungi can act as pathogens. human diseases include ringworm and athlete s foot plant diseases include Dutch elm disease

23 Fungi may be decomposers, pathogens, or mutualists. Fungi can act as mutualists. lichens form between fungi and algae mycorrhizae form between fungi and plants

24 Fungi may be decomposers, pathogens, or mutualists. Fungi can act as mutualists. relationships form between fungi and some insects

25 Fungi are studied for many purposes. Fungi are useful in several ways. as food as antibiotics as model systems for molecular biology