CHOOSE ONE ANSWER

Question

A single gene mutation in cats can result in curly ears (see image).

The cats are healthy and normal beyond the ear structure.

The curly ear trait is recessive, and the allele for curly ears is $

and the allele for regular ears is S.

Select the best response from the options below.

American Curl Cat Breed Information

a
A - the phenotype for S$ is curly ears
b
B - the phenotype for $$ is curly ears
c
C - the genotype S$ results in a cat with regular ears
d
D - the phenotype SS results in a deadly genotype
e
F - B and C are correct

Answer 1

To analyze the options, let's clarify the genetics involved:

• The curly ear trait is noted as recessive, which means the allele for curly ears must be homozygous recessive (i.e., $$) for a cat to display the trait.
• The regular ear trait is represented by the dominant allele S. Therefore, an individual with at least one S allele (genotypes S$, or SS) would have regular ears.

Now let's evaluate the options:

• A - the phenotype for S$ is curly ears: This is incorrect because S$ would have regular ears since S is dominant.
• B - the phenotype for $$ is curly ears: This is correct because homozygous $$ results in curly ears.
• C - the genotype S$ results in a cat with regular ears: This is correct because S is dominant, so S$ would show the regular phenotype.
• D - the phenotype SS results in a deadly genotype: There is no mention of SS being deadly in the information provided, so this statement can't be determined as correct.
• F - B and C are correct: Since both statements B and C are indeed correct.

Given this analysis, the best response is:

F - B and C are correct.