6. Coat color in gophers is determined to some extent by two independently assorting but interacting...

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6. Coat color in gophers is determined to some extent by two independently assorting but interacting gene loci. Dominant gene B at one locus allows the formation of black pigment while its allele b inhibits pigment formation giving rise to an albino coat when homozygous. The other locus, A, allow pigment to be deposited in an agouti pattern. If the gopher's genotype is aa, only the black pigment pattern occurs in the fur. a) what do you think is the developmental (biochemical) pathway that leads to agouti coat pattern? b) If you take two heterozygous gophers, after mating, what phenotypes would be expected and if you had 160 total progeny what numbers in each phenotypic class? c) If you crossed AaBb with aabb mice and had 160 progeny again, what numbers in each phenotypic class would you expect? 7. If a series of 4 alleles exists in a given diploid species, how many alleles would be present in: a) a chromosome? b) a pair of chromosomes? c) an individual member of the species? How many genotypic combinations would occur in the entire species? 8. In foxes, two alleles of a single gene, P and p, may results in lethality (PP) platinum coat (Pp) or silver coat (pp). What ratio is obtained when platinum foxes are bred? If the P allele behaving dominantly or recessively in causing (a) lethality and (b) coat color? 6. Coat color in gophers is determined to some extent by two independently assorting but interacting gene loci. Dominant gene B at one locus allows the formation of black pigment while its allele b inhibits pigment formation giving rise to an albino coat when homozygous. The other locus, A, allow pigment to be deposited in an agouti pattern. If the gopher's genotype is aa, only the black pigment pattern occurs in the fur. a) what do you think is the developmental (biochemical) pathway that leads to agouti coat pattern? b) If you take two heterozygous gophers, after mating, what phenotypes would be expected and if you had 160 total progeny what numbers in each phenotypic class? c) If you crossed AaBb with aabb mice and had 160 progeny again, what numbers in each phenotypic class would you expect? 7. If a series of 4 alleles exists in a given diploid species, how many alleles would be present in: a) a chromosome? b) a pair of chromosomes? c) an individual member of the species? How many genotypic combinations would occur in the entire species? 8. In foxes, two alleles of a single gene, P and p, may results in lethality (PP) platinum coat (Pp) or silver coat (pp). What ratio is obtained when platinum foxes are bred? If the P allele behaving dominantly or recessively in causing (a) lethality and (b) coat color?

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Solution Rewrite the fraction B 1 x1 x1 x1 ... View the full answer