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Two different female Drosophila were isolated, each heterozygous for the autosomally linked genes b (black body), d (dachs tarsus), and c (curved wings). These genes are in the order d—b—c, with b being closer to d than to c. Shown here is the genotypic arrangement for each female along with the various gametes formed by both:
Identify which categories are noncrossovers (NCOs), single crossovers (SCOs), and double crossovers (DCOs) in each case. Then, indicate the relative frequency in which each will be produced.
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