Bio Exam Practice Quiz!

50 Questions | Total Attempts: 83

SettingsSettingsSettings
Please wait...
Biology Quizzes & Trivia

It might not be as easy as you think but just try it out to see how you will do, Let's this knowledgeable quiz now!


Questions and Answers
  • 1. 
    Which of the following is a true statement concerning genetic variation?
    • A. 

      It is created by the direct action of natural selection.

    • B. 

      It arises in response to changes in the environment

    • C. 

      It must be present in a population before natural selection can act upon the population.

    • D. 

      It tends to be reduced by the processes involved when diploid organisms produce gametes.

    • E. 

      A population that has a higher average heterozygosity has less genetic variation than one with a lower average

  • 2. 
    In the formula for determining a population’s genotype frequencies, the 2 in the term 2pq is necessary because  
    • A. 

      The population is diploid.

    • B. 

      Heterozygotes can come about in two ways.

    • C. 

      The population is doubling in number.

    • D. 

      Heterozygotes have two alleles.

  • 3. 
    During an individual oganism’s lifetime, which of these is most likely to help the organism respond properly to changes in its environment?
    • A. 

      Microevolution

    • B. 

      Change in allele or gene frequency

    • C. 

      Change in gene expression

    • D. 

      Change in average heterozygosity

  • 4. 
    Which of the following types of reproductive barriers separates a pair of species that could interbreed except that one mates at dusk and the other at dawn?
    • A. 

      Temporal isolation

    • B. 

      Habitat isolation

    • C. 

      Behavioral isolation

    • D. 

      mechanical isolation

    • E. 

      Gametic isolation

  • 5. 
    Evolution
    • A. 

      Must happen, due to organisms’ innate desire to survive.

    • B. 

      Must happen whenever a population is not well-adapted to its environment

    • C. 

      Can happen whenever any of the conditions for Hardy-Weinberg equilibrium are not met.

    • D. 

      Requires the operation of natural selection.

    • E. 

      Requires that populations become better suited to their environments.

  • 6. 
    Over time, the movement of people on Earth has steadily increased. This has altered the course of human evolution by increasing
    • A. 

      Nonrandom mating

    • B. 

      Geographic isolation.

    • C. 

      Genetic drift.

    • D. 

      Gene flow

  • 7. 
    During breeding season, one should expect female house finches to prefer to mate with males with the brightest red feathers. Which of the following terms are appropriately applied to this situation?
    • A. 

      Sexual selection

    • B. 

      Mate choice

    • C. 

      Intersexual selection

    • D. 

      All of the above

    • E. 

      Only A and B

  • 8. 
    Which of the following statements best summarizes evolution as it is viewed today?
    • A. 

      It represents the result of selection for acquired characteristics.

    • B. 

      It is synonymous with the process of gene flow.

    • C. 

      It is descent of humans from present-day great apes

    • D. 

      It is the differential survival and reproduction of the most-fit phenotypes.

  • 9. 
    Which of the following is most likely to produce an African butterfly species in the wild whose members have one of two strikingly different color patterns?
    • A. 

      Artificicial selection

    • B. 

      Directional selection

    • C. 

      Stabilizing selection

    • D. 

      Disruptive selection

    • E. 

      Sexual selection

  • 10. 
    Which of the following must exist in a population before natural selection can act upon that population?
    • A. 

      Genetic variation among individuals

    • B. 

      Variation among individuals caused by environmental factors

    • C. 

      Sexual reproduction

    • D. 

      Three of the responses are correct

    • E. 

      Two of the responses are correct

  • 11. 
    Frequently, a group of related species will each have a unique courtship ritual that must be performed correctly for both partners to be willing to mate. Such a ritual constitutes a_________ , _________ reproductive barrier.
    • A. 

      Mechanical . . . postzygotic

    • B. 

      Behavioral . . . prezygotic

    • C. 

      Mechanical . . . prezygotic

    • D. 

      Temporal . . . prezygotic

    • E. 

      Gametic . . . postzygotic

  • 12. 
    The recessive allele that causes phenylketonuria (PKU) is harmful, except when an infant’s diet lacks the amino acid phenylalanine. What maintains the presence of this harmful allele in a populations gene pool?
    • A. 

      Heterozygote advantage

    • B. 

      Stabilizing selection

    • C. 

      Diploidy

    • D. 

      Balancing selection

  • 13. 
    The largest unit within which gene flow can readily occur is a
    • A. 

      Population

    • B. 

      Species

    • C. 

      Genus

    • D. 

      Hybrid

    • E. 

      Phylum

  • 14. 
    Natural selection changes allele frequencies because some _________ survive and reproduce more successfully than others.
    • A. 

      Alleles

    • B. 

      Loci

    • C. 

      Gene pool

    • D. 

      Species

    • E. 

      Individuals

  • 15. 
    No two people are genetically identical, except for identical twins. The main source of genetic variation among human individuals is
    • A. 

      New mutations that occurred in the preceding generation.

    • B. 

      Genetic drift due to the small size of the population.

    • C. 

      Reshuffling of alleles in sexual reproduction.

    • D. 

      Geographic variation within the population.

    • E. 

      Environmental effects.

  • 16. 
    Sexual dimorphism is most often a result of
    • A. 

      Pansexual selection.

    • B. 

      Stabilizing selection.

    • C. 

      Intrasexual selection

    • D. 

      Intersexual selection

    • E. 

      Artificial selection

  • 17. 
    Which of the various species concepts distinguishes two species based on the degree of genetic exchange between their gene pools?
    • A. 

      Phylogenetic

    • B. 

      Ecological

    • C. 

      Biological

    • D. 

      Morphological

  • 18. 
    Dog breeders maintain the purity of breeds by keeping dogs of different breeds apart when they are fertile. This kind of isolation is most similar to which of the following reproductive isolating mechanisms?
    • A. 

      Reduced hybrid fertility

    • B. 

      Hybrid breakdown

    • C. 

      Mechanical isolation

    • D. 

      Habitat isolation

    • E. 

      Gametic isolation

  • 19. 
    Which of the following would a biologist describe as microevolution?
    • A. 

      The formation of new species

    • B. 

      The extinction of species

    • C. 

      Dramatic biological changes, such as the origin of flight, within a taxon

    • D. 

      The generation of biodiversity

    • E. 

      A change in allele frequencies within the gene pool of a population

  • 20. 
    Two species of frogs belonging to the same genus occasionally mate, but the offspring fail to develop and hatch. What is the mechanism for keeping the two frog species separate?
    • A. 

      The postzygotic barrier called hybrid inviability

    • B. 

      The postzygotic barrier called hybrid breakdown

    • C. 

      The prezygotic barrier called hybrid sterility

    • D. 

      Gametic isolation

  • 21. 
    According to the concept of punctuated equilibrium, the “sudden” appearance of a new species in the fossil record means that
    • A. 

      The species is now extinct.

    • B. 

      Speciation occurred instantaneously.

    • C. 

      Speciation occurred in one generation.

    • D. 

      Speciation occurred rapidly in geologic time.

    • E. 

      The species will consequently have a relatively short existence, compared with other species

  • 22. 
    Speciation
    • A. 

      Occurs at such a slow pace that no one has ever observed the emergence of new species.

    • B. 

      Occurs only by the accumulation of genetic change over vast expanses of time.

    • C. 

      Must begin with the geographic isolation of a small, frontier population. must begin with the geographic isolation of a small, frontier population.

    • D. 

      And microevolution are synonymous.

    • E. 

      Can involve changes to a single gene.

  • 23. 
    Which of the following statements about speciation is correct?
    • A. 

      The goal of natural selection is speciation.

    • B. 

      When reunited, two allopatric populations will interbreed freely if speciation has occurred.

    • C. 

      Natural selection chooses the reproductive barriers for populations.

    • D. 

      Prezygotic reproductive barriers usually evolve before postzygotic barriers.

    • E. 

      Speciation is a basis for understanding macroevolution.

  • 24. 
    In order for speciation to occur, what must be true?
    • A. 

      The number of chromosomes in the gene pool must change.

    • B. 

      Changes to centromere location or chromosome size must occur within the gene pool.

    • C. 

      Large numbers of genes that affect a single phenotypic trait must change.

    • D. 

      Large numbers of genes that affect numerous phenotypic traits must change.

    • E. 

      At least one gene, affecting at least one phenotypic trait, must change.

  • 25. 
    Sea urchins release their gametes into the water without courtship. Which of these reproductive isolation mechanisms might operate for sea urchin species?
    • A. 

      Behavioral isolation

    • B. 

      Gametic isolation

    • C. 

      Habitat isolation

    • D. 

      Mechanical isolation

Back to Top Back to top