CONCEPTS OF BIOLOGY 07

  1. CONCEPTS OF BIOLOGY 07
    1. Figure 7.2 If a mutation occurs so that a fungus
    is no longer able to produce a minus mating type,
    will it still be able to reproduce?
    Yes, it will be able to reproduce asexually
  2. CONCEPTS OF BIOLOGY 07
    2. What is a likely evolutionary advantage of sexual reproduction over asexual reproduction?

    sexual reproduction involves fewer steps

    less chance of using up the resources in a given environment

    sexual reproduction results in greater variation in the offspring

    sexual reproduction is more cost-effective
    sexual reproduction results in greater variation in the offspring
  3. CONCEPTS OF BIOLOGY 07
    3. Which type of life cycle has both a haploid and diploid multicellular stage?

    an asexual life cycle

    diploid-dominanty

    haploid-dominant

    alternation of generations
    alternation of generations
  4. CONCEPTS OF BIOLOGY 07
    4. Which event leads to a diploid cell in a life cycle?

    meiosis
    fertilization
    alternation of generations
    mutation
    fertilization
  5. CONCEPTS OF BIOLOGY 07
    5. Meiosis produces ________ daughter cells.

    two haploid
    two diploid
    four haploid
    four diploid
    four haploid
  6. CONCEPTS OF BIOLOGY 07
    6. At which stage of meiosis are sister chromatids separated from each other?

    prophase I
    prophase II
    anaphase I
    anaphase II
    anaphase II
  7. CONCEPTS OF BIOLOGY 07
    7. The part of meiosis that is similar to mitosis is ________.

    meiosis I
    anaphase I
    meiosis II
    interkinesis
    meiosis II
  8. CONCEPTS OF BIOLOGY 07
    8. If a muscle cell of a typical organism has 32
    chromosomes, how many chromosomes will be in
    a gamete of that same organism?

    8
    16
    32
    64
    16
  9. CONCEPTS OF BIOLOGY 07
    9. The genotype XXY corresponds to:

    Klinefelter syndrome
    Turner syndrome
    Triplo-X
    Jacob syndrome
    Klinefelter syndrome
  10. CONCEPTS OF BIOLOGY 07
    10. Abnormalities in the number of X chromosomes tend to be milder than the same abnormalities in autosomes because of ________.

    deletions
    nonhomologous recombination
    synapsis
    X inactivation
    X inactivation
  11. CONCEPTS OF BIOLOGY 07
    11. Aneuploidies are deleterious for the individual because of what phenomenon?

    nondisjunction
    gene dosage
    meiotic errors
    X inactivation
    gene dosage
  12. CONCEPTS OF BIOLOGY 07
    12. Explain the advantage that populations of sexually reproducing organisms have over asexually reproducing organisms?
    The offspring of sexually reproducing organisms are all genetically unique.
  13. sexually reproducing organisms may have more successful survival of offspring in environments that
    change than asexually reproducing organisms, whose offspring are all genetically identical.
  14. the rate of adaptation of sexually reproducing organisms is higher, because of their increased variation...
  15. ...This may allow sexually reproducing organisms to adapt more quickly to competitors and
    parasites, who are evolving new ways to exploit or outcompete them
  16. CONCEPTS OF BIOLOGY 07
    13. Describe the two events that are common to all sexually reproducing organisms and
    how they fit into the different life cycles of those organisms.
    • The two events common to all sexually reproducing organisms
    • are meiosis and fertilization. Meiosis reduces a diploid cell to a haploid state. The haploid cell may divide
    • mitotically to produce an organism, some of whose cells will combine during fertilization, or the haploid
    • cells produced by meiosis may immediately combine in fertilization to produce a diploid cell that divides
    • to produce an organism
  17. CONCEPTS OF BIOLOGY 07
    14. Explain how the random alignment of homologous chromosomes during metaphase I contributes to variation in gametes produced by meiosis.
    • Random alignment leads to new combinations of traits. The chromosomes that
    • were originally inherited by the gamete-producing individual came equally from the egg and the sperm. In
    • metaphase I, the duplicated copies of these maternal and paternal homologous chromosomes line up across
    • the center of the cell to form a tetrad. The orientation of each tetrad is random. There is an equal chance
    • that the maternally derived chromosomes will be facing either pole. The same is true of the paternally
    • derived chromosomes. The alignment should occur differently in almost every meiosis. As the homologous
    • chromosomes are pulled apart in anaphase I, any combination of maternal and paternal chromosomes will
    • move toward each pole. The gametes formed from these two groups of chromosomes will have a mixture
    • of traits from the individual’s parents. Each gamete is unique.
  18. CONCEPTS OF BIOLOGY 07
    15. In what ways is meiosis II similar to and different from mitosis of a diploid cell?
    • The two divisions are similar in that the
    • chromosomes line up along the metaphase plate individually, meaning unpaired with other chromosomes
    • (as in meiosis I). In addition, each chromosome consists of two sister chromatids that will be pulled apart.
    • The two divisions are different because in meiosis II there are half the number of chromosomes that are
    • present in a diploid cell of the same species undergoing mitosis. This is because meiosis I reduced the number
    • of chromosomes to a haploid state.
  19. CONCEPTS OF BIOLOGY 07
    16. Individuals with trisomy 21 are more likely to survive to adulthood than individuals with trisomy
    Based on what you know about aneuploidies
    from this module, what can you hypothesize about
    chromosomes 21 and 18?
    • The problems caused by trisomies arise because the genes on the
    • chromosome that is present in three copies produce more product than genes on chromosomes with only two
    • copies. The cell does not have a way to adjust the amount of product, and the lack of balance causes problems
    • in development and the maintenance of the individual. Each chromosome is different, and the differences in
    • survivability could have to do with the numbers of genes on the two chromosomes. Chromosome 21 may
    • be a smaller chromosome, so there are fewer unbalanced gene products. It is also possible that chromosome
    • 21 carries genes whose products are less sensitive to differences in dosage than chromosome 18. The genes
    • may be less involved in critical pathways, or the differences in dosage may make less of a difference to those
    • pathways.
Author
ianquinto
ID
351714
Card Set
CONCEPTS OF BIOLOGY 07
Description
CONCEPTS OF BIOLOGY 07
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