In dogs, curly fur (C) is dominant to straight fur (c) and large size (L) is dominant to small size (I). A dog that is heterozygous for both traits (CcLI) is crossed with a dog that is homozygous dominant for curly fur and homozygous recessive for size (CCII). How many different phenotypes are their offspring expected to show? 6 4

To determine the number of different phenotypes the offspring are expected to show, we need to consider the possible combinations of alleles they can inherit from their parents.<br /><br />Given that the first dog is heterozygous for both traits (CcLI), it can produce gametes with the following combinations of alleles: Cc, CI, cI, and ci.<br /><br />The second dog is homozygous dominant for curly fur (CC) and homozygous recessive for size (II), so it can only produce gametes with the combination of alleles CI.<br /><br />When we cross these gametes, we can create a Punnett square to visualize the possible combinations of alleles in the offspring:<br /><br />| | CI | CI | CI | CI |<br />|-------|-----|-----|-----|-----|<br />| Cc | CCI | CCI | CCI | CCI |<br />| CI | CCI | CCI | CCI | CCI |<br />| cI | cCI | cCI | cCI | cCI |<br />| ci | cCI | cCI | cCI | cCI |<br /><br />From the Punnett square, we can see that all the offspring will have the same combination of alleles (CCI), which corresponds to the phenotype of curly fur and large size.<br /><br />Therefore, the offspring are expected to show only 1 phenotype.