The symbol "Cy" represents a mutant allele in Drosophila that confers curly wings instead of normal, straight wings (i. e., the wildtype condition).

Part A

Because the symbol for this mutant allele is capitalized, you can immediately infer that this mutation must be:

a. dominant

b. recessive

Part B

Which symbol refers to the wildtype form of this allele?

a. cy

b. Cy+

c. +

d. Cy

a. Dominant

b. Cy+, +

Explanation:

The mutation explained in the question is written with capital letters as "Cy". Since the mutation is denoted with upper case letters, it should be dominant over the wild type phenotype.

In genetics, the wild type phenotype is mutated to produce one or more mutant phenotypes. To distinguish the wild type alleles from the mutated alleles, the former ones are written as "+" or "+" is written as a superscript to the letters denoting the mutant allele. Therefore, the wild type allele for the gene can be written as "+" or as "Cy⁺". Here, "+" is superscript to "Cy".