In cats, the allele for curled ears (C) is dominant over hte allele for normal ears (c). The allele for black colour (B) is dominant over the allele for grey colour (b). A cross occurs between two cats that are both heterozygous for these unlinked traits. Using a Punnett grid, predict the ratio of phenotypes of offspring in the next generation

Respuesta :

Answer:

9:3:3:1

Explanation:

In the given question, the two genes are unlinked which are controlled by dominant and recessive allele.

Trait- Ear curling

1. Curled ears- C, genotype will be- CC or Cc

2. Normal ears-c, genotype will be- cc

Trait- color

1. Black colour- B,genotype will be- BB or Bb

2. Grey colour- b, genotype will be- bb

Now, if cross between heterozygote will be performed

    CcBb x CcBb

then allele will be CB, Cb, cB and cb

Now punnett square cross will be-

             M/F      CB           Cb          cB          cb

             CB   CCBB      CCBb     CCBb     CcBb

             Cb      CCBb      CCbb     CcBb      Ccbb

            cB      CcBb       Ccbb       ccBb      ccBb

            cb      CcBb         Ccbb      ccBb      ccbb

On the basis of this phenotypic ratio will be-

  • 9 black and curled
  • 3 black not curled
  • 3 brown and curled
  • 1 brown and not curled

Thus, 9:3:3:1 is correct.