The pedigree below tracks a genetic abnormality through five generations of a family tree. The trait, polydactyly, is characterized by extra fingers (left), toes, or both. The pedigree shows the number of fingers on each hand in black; toes on each foot, in red. male female unknown gender marriage/mating individual with the trait being studied I, II, III, IV... generation offspring Standard symbols used in pedigrees. 1 II *Gene not expressed in this carrier. III IV V (a) Using the pedigree, describe the genotypes of the parents for the trait polydactyly in generation I. (b) (6) Explain how humans are able to produce gametes that are haploid. (c) According to the pedigree, explain the inheritance pattern of the genetic abnormality polydactyly.



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