Answer:
Explanation:
Geneticists use letters to represent alleles of different characters.
(Alleles: one of the two or more alleles of a character.)
A single letter is used to represent both the alleles of a particular character.
A capital letter represents a dominant allele, while a small letter represents a recessive one.
<u>The letters do not just have one standard representation</u>. same letter can be used to represent different characters. However, the letters may relate to the allele. For example: the letter 'B' can be used to represent Brown eyes.
If a boy exhibits a sex-linked trait that is carried on the X chromosomes, his mother carried at-least one allele for that trait.
The boy has a X chromosome inherited from his mother and he inherited Y chromosome from his father. So, his mother must carried at least one allele for that trait because he exhibits a sex linked trait that is carried on X chromosome.
