Biology for IGCSE & O level - Variation And Selection (Section 2)

  • 1
    Which of the following is a key factor contributing to the struggle for survival?
    Одговорити
    (A)
    Limited resources
  • 2
    What is an adaptive feature?
    Одговорити
    (C)
    A feature that helps an organism survive and reproduce.
  • 3
    Which of the following statements is correct regarding inheritance in natural selection?
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    (D)
    Only traits that are determined by genes are inherited.
  • 4
    What factor contributes most to the struggle for survival?
    Одговорити
    (B)
    Overproduction of offspring.
  • 5
    What is the main difference between genetic and phenotypic variation?
    Одговорити
    (B)
    Genetic variation refers to the differences in genes, while phenotypic variation refers to the physical or observable traits.
  • 6
    Which term is best defined by the statement: 'A change in the DNA base sequence of a gene'?
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    (B)
    A change in the DNA base sequence of a gene
  • 7
    What is the main difference between inbreeding and outbreeding?
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    (A)
    Inbreeding involves breeding closely related individuals.
  • 8
    Which of the following are necessary for evolution by natural selection to occur?
    Одговорити
    A
    B
    D
  • 9
    Which type of variation would describe the height of plants which grows in the same environment?
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    (D)
    Phenotypic variation.
  • 10
    How does the environment influence the process of natural selection?
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    (A)
    It selects which variations are advantageous.
  • 11
    Which of the following is an example of an adaptive feature found in desert plants?
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    (C)
    Sunken stomata
  • 12
    Which of these scenarios would demonstrate discontinuous variation?
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    (B)
    The colors of sweet pea flowers.
  • 13
    What will happen if a mutation occurs in a sex cell?
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    (B)
    It will affect the next generation.
  • 14
    How does the environment influence phenotype?
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    (C)
    It influences the expression of genes.
  • 15
    What is the key difference between natural selection and selective breeding?
    Одговорити
    (B)
    Natural selection is driven by environmental factors; selective breeding is driven by human choice.
  • 16
    What is a potential consequence of excessive inbreeding?
    Одговорити
    (C)
    Reduced vigor in offspring
  • 17
    What are the main requirements for evolution to occur through natural selection?
    Одговорити
    (B)
    Inheritance, variation, and competition are needed.
  • 18
    How do the differing seed types (light vs. heavy) in the weeds contribute to their survival in a human-dominated environment?
    Одговорити
    (A)
    Lighter seeds are more likely to land on concrete; heavier seeds are more likely to fall close to the parent plant.
  • 19
    What process is responsible for the development of antibiotic resistance?
    Одговорити
    (B)
    Natural selection
  • 20
    In the context of weed seed dispersal, what environmental factor favors heavy seeds?
    Одговорити
    (C)
    Limited open soil areas
  • 21
    What is the primary source of genetic variation in a population?
    Одговорити
    (B)
    Mutation
  • 22
    What is the meaning of the term hybrid vigour?
    Одговорити
    (B)
    Increase the fitness of the offspring.
  • 23
    What is a potential drawback of inbreeding?
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    (C)
    Increased susceptibility to diseases.
  • 24
    What is a key characteristic of discontinuous variation?
    Одговорити
    (C)
    It has distinct categories or groups.
  • 25
    How does antibiotic resistance in bacteria arise?
    Одговорити
    (D)
    All of the above.
  • 26
    What is a gene?
    Одговорити
    (C)
    A segment of DNA that codes for a trait.
  • 27
    What do scientists use to show the range of a continuous variation?
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    (C)
    A histogram
  • 28
    What is the primary driving force behind natural selection?
    Одговорити
    (B)
    Environmental factors.
  • 29
    Which of the following is an example of continuous variation?
    Одговорити
    (C)
    The height of human beings
  • 30
    What type of selection would be used to describe the breeding of the Merino sheep?
    Одговорити
    (B)
    Artificial selection
  • 31
    Which of the following is an example of an adaptive feature for a cactus plant in a desert environment?
    Одговорити
    (D)
    Spines
  • 32
    Which of the following are examples of a desirable feature that farmers use to increase productivity with selective breeding?
    Одговорити
    A
    B
    C
    D
  • 33
    What are the two main methods of carrying out selective breeding?
    Одговорити
    A
    B
  • 34
    What are the two main types of variation that occur within a species?
    Одговорити
    (C)
    Continuous and discontinuous
  • 35
    What happens during the process of natural selection?
    Одговорити
    A
    B
    C
  • 36
    What does overproduction of offspring lead to?
    Одговорити
    (C)
    Competition for resources
  • 37
    What are the two main types of variation within a species?
    Одговорити
    (B)
    Continuous and discontinuous variation
  • 38
    What is the term used to describe the increased health and vigor of offspring resulting from the outbreeding process?
    Одговорити
    (B)
    Hybrid vigor
  • 39
    Which of the following is an example of discontinuous variation?
    Одговорити
    (C)
    Human blood groups
  • 40
    Why is it necessary for drug companies to find and develop new types of antibiotics?
    Одговорити
    (D)
    Many bacteria are resistant to some antibiotics.
  • 41
    Which of the following is a characteristic of discontinuous variation?
    Одговорити
    (A)
    Individuals fall into distinct categories.
  • 42
    Which is an example of a discontinuous variation?
    Одговорити
    (C)
    Human Blood Group
  • 43
    What is the primary role of mutations in the context of evolution?
    Одговорити
    (B)
    To create new alleles, which can lead to genetic variation.
  • 44
    Which of the following is a key feature that farmers improve by breeders in cereal crops?
    Одговорити
    (B)
    Higher yield.
  • 45
    Which of the following best describes the process of natural selection?
    Одговорити
    (B)
    Organisms with advantageous traits are more likely to survive and reproduce.
  • 46
    What is the main difference between artificial and natural selection?
    Одговорити
    (B)
    Artificial selection is driven by human actions, natural selection is driven by the environment.
  • 47
    Which of the following is a key characteristic of a population undergoing natural selection?
    Одговорити
    (C)
    There is variation among individuals in the population.
  • 48
    What is the most accurate description of a 'gene'?
    Одговорити
    (B)
    A segment of DNA that codes for a trait
  • 49
    Which of the following is a key aspect of the process of natural selection?
    Одговорити
    (B)
    Environmental factors influence which traits are advantageous.
  • 50
    What causes new alleles in a gene pool?
    Одговорити
    (B)
    Mutations