Environmental Science Exam 3 Study Guide
54 Questions
102 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

The evolution of populations due to chance is?

  • Natural selection
  • Genetic drift (correct)
  • Genetic variation
  • Has more effect in large populations than in small populations
  • Gene flow

    • If color is an inherited trait in beetles, and birds are more likely to eat brown beetles than green beetles, what happens?

  • The frequency of the green allele will increase. (correct)
  • The frequency of the brown allele will increase.
  • This causes the population to evolve due to genetic drift.
  • The frequencies of the brown and green alleles will not change.
  • This causes the population to evolve due to gene flow.

    • In a population with brown and green alleles for color, genetic drift?

  • Always increases the frequency of brown alleles in the population
  • Causes populations to become better adapted to their environments.
  • Occurs when individuals move into or out of a population, changing the allele frequencies in the population.
  • Has more effect on the evolution of a small population. (correct)
  • Has more effect on the evolution of a large population.

    • Color is an inherited trait in beetles. If brown beetles move into a population from a nearby island, which statement is correct?

    <p>Gene flow causes the frequency of the brown allele to increase.</p> Signup and view all the answers

    Which of the following is an example of natural selection?

    <p>Green beetles leave more offspring than brown beetles because they are better at finding food.</p> Signup and view all the answers

    Generation-to-generation change in the allele frequencies in a population is?

    <p>Microevolution</p> Signup and view all the answers

    An allele is?

    <p>A particular version of a gene</p> Signup and view all the answers

    A population is?

    <p>Members of the same species occupying the same area at the same time</p> Signup and view all the answers

    How many alleles do you inherit for each genetic trait?

    <p>2</p> Signup and view all the answers

    Allelic frequencies change in?

    <p>A population</p> Signup and view all the answers

    Which of the following events could NOT be caused by a population bottleneck?

    <p>Increased population size</p> Signup and view all the answers

    Feathers either play a role, or may have played a role, in?

    <p>All of these</p> Signup and view all the answers

    ____ is rapid, branching speciation under conditions in which there is little competition.

    <p>Adaptive radiation</p> Signup and view all the answers

    Mass extinctions create conditions that promote?

    <p>Adaptive radiation</p> Signup and view all the answers

    The appearance of an evolutionary novelty often promotes?

    <p>Adaptive radiation</p> Signup and view all the answers

    The only process that can add new genes and therefore new variations to a species is?

    <p>Mutation</p> Signup and view all the answers

    Two organisms living in the same geographical area, being genetically similar, can breed with each other. Which statement is correct?

    <p>These organisms are members of the same species.</p> Signup and view all the answers

    To belong to the same species, individuals must?

    <p>Be able to reproduce and have fertile offspring</p> Signup and view all the answers

    Which type of selection helps to preserve the status quo, genetically speaking?

    <p>Stabilizing selection</p> Signup and view all the answers

    An excellent example of selective or artificial breeding by humans is?

    <p>The diversity of dog breeds in the world today</p> Signup and view all the answers

    Which statement most accurately describes a phylogenetic tree?

    <p>A phylogenetic tree is a branching diagram used to illustrate a scientist's hypothesis about how divergence took place among evolutionary lines.</p> Signup and view all the answers

    A single, small population that only exists in one place on the planet is considered?

    <p>Endemic</p> Signup and view all the answers

    Which population is most vulnerable to extinction?

    <p>A small, endemic population</p> Signup and view all the answers

    The sixth mass extinction event is likely being caused by?

    <p>Human-induced events</p> Signup and view all the answers

    Which explains the extinction of upwards of 90% of species in existence over a short period of time?

    <p>Mass extinction events</p> Signup and view all the answers

    Extinction is a(n) _____ process; human activity can affect the _____ at which extinction occurs.

    <p>Natural, rate</p> Signup and view all the answers

    Which of the following is considered a community?

    <p>Several interacting species living in the same area</p> Signup and view all the answers

    Which is the broadest level of ecological organization?

    <p>The biosphere</p> Signup and view all the answers

    A _____ is defined as the living and nonliving elements around an organism.

    <p>Habitat</p> Signup and view all the answers

    Starting from the smallest level of ecological organization to the highest, the order should go organism,?

    <p>Population, community, ecosystem, biosphere</p> Signup and view all the answers

    An ideal habitat with unlimited resources is associated with?

    <p>Exponential growth</p> Signup and view all the answers

    The maximum population a habitat can support is its?

    <p>Carrying capacity</p> Signup and view all the answers

    Logistic growth involves?

    <p>Population growth slowing down as the population approaches carrying capacity</p> Signup and view all the answers

    In exponential growth?

    <p>Population size grows faster and faster as the population gets bigger</p> Signup and view all the answers

    Which of the following would NOT cause population size to decrease?

    <p>Increased birth rate</p> Signup and view all the answers

    The innate reproductive capacity of a species is its?

    <p>Biotic potential</p> Signup and view all the answers

    The carrying capacity is?

    <p>The maximum population size that a given environment can sustain</p> Signup and view all the answers

    What describes the number of individuals in a population per unit area?

    <p>Population density</p> Signup and view all the answers

    When looking at the distribution of a population, we might find a uniform distribution when?

    <p>Individuals are competing for an evenly distributed resource such as space</p> Signup and view all the answers

    Density-dependent factors?

    <p>Have a greater impact at higher population densities</p> Signup and view all the answers

    Consider a population of fish in the ocean. What would be a limiting factor for such a population?

    <p>Dissolved oxygen levels</p> Signup and view all the answers

    Assuming a population grows by a fixed percentage each year, which starting population would experience the biggest increase in its population?

    <p>2,000 individuals</p> Signup and view all the answers

    Which of the following would be the most effective action for protecting biodiversity?

    <p>Do all of the above</p> Signup and view all the answers

    Which includes both organisms and the physical environment?

    <p>Ecosystem</p> Signup and view all the answers

    K-strategists are likely to have higher dispersal rates than r-strategists.

    <p>False</p> Signup and view all the answers

    The bubonic plague, which swept through Europe in the 14th century, is an example of _____ on human population growth.

    <p>Density-dependent control</p> Signup and view all the answers

    A(n) _____ always has a narrow niche.

    <p>Specialist species</p> Signup and view all the answers

    Natural selection involves all of these EXCEPT:

    <p>All individuals in a population have the same likelihood of dying over a given period of time.</p> Signup and view all the answers

    Which is required for speciation to occur?

    <p>Separation of one part of the population from another</p> Signup and view all the answers

    Factors capable of driving natural selection include:

    <p>All of the above.</p> Signup and view all the answers

    Match the following ecological terms with their definitions:

    <p>Ecological niche = Roles of an organism in its environment Habitat = Place where an organism lives Biodiversity = Variety of life in a specific area Population density = Number of individuals in a given area</p> Signup and view all the answers

    What is defined as the maximum population size that a given environment can sustain?

    <p>Carrying capacity</p> Signup and view all the answers

    What is defined as the innate reproductive capacity of a species?

    <p>Biotic potential</p> Signup and view all the answers

    What describes the number of individuals in a population per unit area?

    <p>Population density</p> Signup and view all the answers

    Study Notes

    Evolution and Genetics

    • Genetic drift refers to evolution due to chance; it significantly impacts small populations.
    • When brown beetles are preferentially preyed upon by birds, the frequency of the green allele in the population increases due to natural selection favoring green beetles.
    • Gene flow occurs when individuals move into a population, such as brown beetles joining an existing group, resulting in increased frequency of the brown allele.

    Natural Selection

    • Natural selection is demonstrated when organisms with advantageous traits, like green beetles better at finding food, survive more effectively.
    • Microevolution is defined as generation-to-generation changes in allele frequencies within a population.

    Population and Alleles

    • An allele represents a specific version of a gene, while a population consists of individuals of the same species in a particular area.
    • Individuals inherit two alleles for each genetic trait, one from each parent, affecting traits in the offspring.

    Ecological Concepts

    • Allelic frequencies change only within a population, not at the individual or single-cell level.
    • A population bottleneck can lead to reductions in genetic variability and loss of alleles, but not increased population size.
    • A community consists of interacting species in a shared area; the broadest level of ecological organization is the biosphere, encompassing all ecosystems.

    Extinction and Biodiversity

    • The sixth mass extinction is primarily driven by human activities, altering habitats and contributing to species loss.
    • Endemic populations, which are small and localized, are particularly vulnerable to extinction.

    Population Dynamics

    • The carrying capacity of an environment is its maximum sustainable population size, influenced by resource availability and environmental resistance.
    • Density-dependent factors have a greater impact on population size at higher population densities, while density-independent factors affect populations regardless of size.

    Growth Patterns

    • Exponential growth occurs when populations expand rapidly with unlimited resources, while logistic growth slows as populations approach carrying capacity.
    • Biotic potential refers to the maximum reproductive capacity of a species, influencing population dynamics.

    Speciation and Natural Selection Drivers

    • Speciation often requires the separation of one part of a population from another, allowing for divergent evolution and adaptation.
    • Natural selection is influenced by various factors, including competition, disease, and environmental extremes.

    Ecological Niches and Habitats

    • An organism's ecological niche encompasses its habitat and the role it plays in the ecosystem, while specialists occupy narrow niches, unlike generalists which adapt to a wider range.
    • Phylogenetic trees illustrate hypotheses about evolutionary relationships among species based on genetic and anatomical similarities.

    Conservation Strategies

    • Effective biodiversity protection involves conservation, preservation, and sustainable practices, such as ecotourism.

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Description

    Prepare for your Environmental Science Exam 3 with this study guide consisting of flashcards that cover important concepts such as genetic drift, natural selection, and allele frequencies. Each card features key definitions and explanations to aid in your understanding of evolutionary mechanisms.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser