There are organisms that go through meiosis but do not undergo recombination when forming haploid gametes. Which of the following statements correctly describes the gametes produced by such an organism
(Assume that these organisms are diploid, that each of the two homologous chromosomes are genetically distinct as typically found in the wild, and that these organisms have more than one chromosome.)
(a) All gametes formed during a single meiosis will be identical.
(b) Due to the random assortment of homologs, each of the gametes formed during a single meiosis will be different.
(c) This organism could potentially produce 2n genetically distinct gametes, where n is its haploid number of chromosomes.
(d) The fusion of any two gametes produced by such an organism that does not undergo recombination during meiosis will create a cell that is genetically identical to that individual.
Choice (c) is correct. Although it is true that the homologs will randomly assort in meiosis I [choice (b)], this will only create two different types of genetic combinations in a single meiosis. Thus, four gametes will be produced, and the two products of meiosis II will be genetically identical to each other. Because the two homologous chromosomes are genetically distinct, the four gametes formed during meiosis cannot be identical [choice (a)]. Because the two homologs are genetically distinct and segregate randomly in meiosis I, the fusion of any two gametes produced by an individual will lead to unique combinations of maternal and paternal chromosomes, and thus the resulting cell will not be genetically identical to the individual [choice (d)].
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