Biology Chapter 8 Flashcards
10 Questions
100 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

What is evolution defined as?

  • A change in the frequency of alleles in a population over time. (correct)
  • A progressive 'ladder' of changes from most primitive organisms to most advanced organisms.
  • Survival of the fittest.
  • A change in a morphological trait of an individual during its lifetime.
  • A change in the frequency of a morphological trait in a population over time.
  • To demonstrate evolution by natural selection, all of the following conditions must be satisfied EXCEPT?

  • Variation for a trait.
  • Heritability of a trait.
  • Differential reproductive success.
  • Genetic drift. (correct)
  • All of the above are necessary for evolution by natural selection.
  • ______________ selection favors organisms that have character values at both extremes of the phenotypic distribution.

    Disruptive

    Which of the following statements is NOT consistent with evolution by natural selection?

    <p>Individuals change during their lifespans to fit their environment better, and these changes can be inherited by their offspring.</p> Signup and view all the answers

    All of the following statements are true about mutations EXCEPT?

    <p>The mutation rate can be affected by exposure to radiation.</p> Signup and view all the answers

    A population is defined as?

    <p>A group of individuals of the same species that live in the same general location and have the potential to interbreed.</p> Signup and view all the answers

    Birth weight in human babies is generally:

    <p>Subject to stabilizing selection.</p> Signup and view all the answers

    The change in genotypic frequency of a fish population after a flash flood is most likely attributable to?

    <p>Genetic drift.</p> Signup and view all the answers

    Which of the following best explains why genetic bottlenecks and founder effects are evolutionarily important?

    <p>Both result in small populations subject to genetic drift.</p> Signup and view all the answers

    The phenotypic trait of polydactyly, associated with Ellis-van Creveld syndrome, is more commonly found in Old Order Amish populations. What is a possible explanation?

    <p>The Old Order Amish experience the 'founder effect,' where all the members of a population descend from a small group of founding individuals.</p> Signup and view all the answers

    Study Notes

    Evolution and Natural Selection

    • Evolution is defined as a change in the frequency of alleles in a population over time.
    • Conditions for evolution by natural selection: variation for a trait, heritability of a trait, and differential reproductive success are essential; genetic drift is not required.
    • Disruptive selection favors organisms at both extremes of a phenotypic distribution.

    Understanding Natural Selection

    • Variation among individuals can be inherited, and natural selection can lead to speciation.
    • Inherited changes in an organism's lifetime adapting to the environment contradicts natural selection principles.

    Mutations and Genetic Variation

    • Mutations serve as the origin of genetic variation; they occur as changes in an organism's DNA and are generally random.
    • Most mutations are neutral or beneficial; however, the mutation rate is not necessarily affected by radiation exposure.

    Population Definitions and Traits

    • A population consists of individuals of the same species that live in the same area and have potential for interbreeding.
    • Human birth weight is typically subject to stabilizing selection, indicating optimal intermediate weights are favored.

    Genetic Drift and Evolutionary Impact

    • Significant changes in genotypic frequency in populations, such as after events like flash floods, are often due to genetic drift.
    • Genetic bottlenecks and founder effects are crucial in evolution, leading to small populations that are susceptible to genetic drift.

    Case Study: Ellis-van Creveld Syndrome

    • Polydactyly, associated with Ellis-van Creveld syndrome, is more prevalent in the Old Order Amish; this may suggest a founder effect where a small group of ancestors contributes disproportionately to the gene pool.

    Studying That Suits You

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

    Quiz Team

    Description

    Test your knowledge on the principles of evolution with these flashcards from Chapter 8. Each card includes key definitions and concepts related to evolutionary biology, focusing on allele frequency and morphological traits in populations. Perfect for revision and enhancing your understanding of evolutionary processes.

    More Like This

    Use Quizgecko on...
    Browser
    Browser