Question

this passage describes one of the coat - texture traits in cats:
selkirk rex cats are known for their curly fur. cats of this breed have coats that are either wavy or tightly curled. fur texture is dependent on the shape of the hair follicle, with curved follicles resulting in curly hairs.
in a group of cats, some individuals have tightly curled fur, some have wavy fur, and some have straight fur. in this group, one of the genes for follicle shape has two alleles. the allele for curved follicles resulting in tightly curled fur ($k^{r}$) is incompletely dominant over the allele for straight follicles resulting in straight fur ($k^{s}$). so heterozygotes have wavy fur.
complete the punnett square to show all possible genotypes of the offspring from a cross between two cats: one with tightly curled fur and one with wavy fur.
$k^{r}$ $k^{s}$
$k^{r}$
$k^{r}$

Explanation:

Step1: Determine the genotypes

The cat with tightly - curled fur has the genotype \(K^{R}K^{R}\) (since tightly - curled fur is \(K^{R}\) and for a homozygous dominant trait, the genotype is \(K^{R}K^{R}\)). The cat with wavy fur has the genotype \(K^{R}K^{S}\) (because heterozygotes \(K^{R}K^{S}\) have wavy fur).

Step2: Fill in the Punnett square

For the first parent (genotype \(K^{R}K^{R}\)), the gametes produced are all \(K^{R}\). For the second parent (genotype \(K^{R}K^{S}\)), the gametes produced are \(K^{R}\) and \(K^{S}\).
When we cross them:

• The top - left box: \(K^{R}\) (from first parent) and \(K^{R}\) (from second parent) gives \(K^{R}K^{R}\)
• The top - right box: \(K^{R}\) (from first parent) and \(K^{S}\) (from second parent) gives \(K^{R}K^{S}\)
• The bottom - left box: \(K^{R}\) (from first parent) and \(K^{R}\) (from second parent) gives \(K^{R}K^{R}\)
• The bottom - right box: \(K^{R}\) (from first parent) and \(K^{S}\) (from second parent) gives \(K^{R}K^{S}\)

Answer:

	\(K^{R}\)	\(K^{S}\)
\(K^{R}\)	\(K^{R}K^{R}\)	\(K^{R}K^{S}\)