Questions and Answers
Define biodiversity and list its four major components.
Biodiversity is the variety of earth's species, the genetics they contain, where they live, and the processes that sustain all life. The four major components are genetic, functional, ecological, and species diversity.
Define biomes and give three examples.
Biomes are large regions with distinct climates and certain species that have adapted to living in them. Examples include forests, deserts, and grasslands.
What is a mutation and what role do mutations play in evolution by natural selection?
Mutations are changes in the DNA molecules of a gene that can be inherited by offspring. They are considered favorable traits that may assist a species in surviving natural selection.
What is adaptation (adaptive trait)?
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What are two limits on evolution by natural selection?
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Describe how geological processes can affect natural selection.
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Distinguish between geographic isolation and reproductive isolation.
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What is an endemic species and why can such a species be vulnerable to extinction?
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Distinguish between background extinction rate and mass extinction.
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Define species diversity and distinguish between species richness and species evenness.
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Explain why species-rich ecosystems tend to be productive and sustainable.
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What are the different types of species? (Select all that apply)
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Study Notes
Biodiversity
- Biodiversity, or biological diversity, refers to the variety of species on Earth, their genetic traits, habitats, and the ecological processes that sustain life.
- Major components of biodiversity include:
- Genetic Diversity: Variation in genetic makeup among individuals within a species.
- Functional Diversity: Different biological processes and functions within ecosystems.
- Ecological Diversity: Variety of ecosystems and habitats in a given area.
- Species Diversity: The number of different species and their abundance in a specific context.
Biomes
- Biomes are large ecological areas with distinct climates, characterized by specific flora and fauna.
- Examples of biomes include:
- Forests: Diverse ecosystems with dense tree coverage.
- Deserts: Arid regions with low rainfall and specially adapted organisms.
- Grasslands: Open areas dominated by grasses with few trees, adapted to grazing and fire.
Mutations and Evolution
- Mutations are genetic changes in the DNA that can be inherited.
- They play a crucial role in evolution by natural selection, often providing advantageous traits that enhance survival and reproduction, allowing those traits to be passed to future generations.
Adaptation
- Adaptation refers to heritable traits that enhance an organism's ability to survive and reproduce in its environment.
- Adaptive traits are critical for maintaining population viability over time.
Limits on Evolution by Natural Selection
- Evolution can only occur if advantageous traits exist within a species or emerge from mutations.
- Large species may struggle to adapt quickly due to longer generation times and larger populations.
Geological Processes and Natural Selection
- Geological processes can isolate species, leading to adaptations necessary for survival in new environments over time.
Isolation and Speciation
- Geographic Isolation: Occurs when a physical barrier separates species, leading to distinct evolutionary paths.
- Reproductive Isolation: Arises when genetic changes occur independently in isolated populations, eventually preventing interbreeding and leading to the emergence of new species.
Endemic Species
- Endemic species are those found exclusively in a specific region.
- They are vulnerable to extinction due to their reliance on localized ecosystems and limited adaptability to new environments.
Extinction Rates
- Background Extinction Rate: The natural, low rate at which species become extinct over time.
- Mass Extinction: A rapid and significant increase in extinction rates, typically caused by catastrophic events.
Species Diversity
- Species diversity encompasses the variety of species within an ecosystem.
- Species Richness: The count of different species in an area.
- Species Evenness: The distribution of individuals among the species; a higher evenness indicates a more balanced ecosystem.
Productivity of Species-Rich Ecosystems
- Ecosystems rich in species tend to be more productive and sustainable due to:
- Diverse species providing varied resources and food.
- Enhanced resilience to environmental stresses, as different species fulfill a range of ecological roles.
Types of Species
- Native Species: Organisms that naturally occur and thrive in a specific ecosystem.
- Nonnative Species: Species that migrate or are introduced to new ecosystems, which can disrupt local balance.
- Indicator Species: Organisms sensitive to environmental changes, useful for assessing ecosystem health.
- Keystone Species: Species that play a critical role in maintaining ecosystem structure and function; their removal can lead to significant shifts in the ecosystem.
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Description
Test your knowledge on biodiversity and the various biomes of the Earth. This quiz covers key concepts such as genetic, functional, ecological, and species diversity, along with different types of ecosystems and their characteristics. Enhance your understanding of the complex interactions that sustain life on our planet.