Two strains of S. cerevisae (yeast) are crossed. One has the genotype A B and the other a b. Which statement correctly describes the tetrads that can be produced by one reciprocal exchange without gene conversion in the dihybrid?
A) Recombination occurs at the four-strand stage to produce a tetrad with A B, A B, a B, and a b chromosomes.
B) Recombination occurs at the four-strand stage to produce a tetrad with A B, A b, a B, and a b chromosomes.
C) Recombination occurs at the two-strand stage to produce a tetrad with A B, A b, a B, and a b chromosomes.
D) Recombination occurs at the two-strand stage to produce a tetrad with A b, A b, a B, and a B chromosomes.
B) Recombination occurs at the four-strand stage to produce a tetrad with A B, A b, a B, and a b chromosomes.
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Which of the following distinguish the field of microbiology from other fields of biology?
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because it is ____.
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