Question

Q:- Wing coloration in the magpie moth, a species

exhibitingthe ZW system of sex chromosomes, is determined by a
locuscarried on the Z chromosome. The dominant allele,L, at this
locusdark wings while the expression of its recessive counterpart,
l,results in wings which are light in color.
a) Cross a homozygous light- winged male with a
dark-wingedfemale and determine the expected F1
,indicating the sexand phenotype of the offspring.
b) Cross a male and female from the F1 to
determinethe expected outcome of the F2
genertaion.

Answer 1

a) All males will have dark wings, all females will have light wings. See attachment

b) Males - 50:50 dark:light, females, 100% dark wings

Step-by-step explanation:

The ZW sex determination system is different from the XY sex determination system. Females are ZW, whereas males are ZZ (in contrast to XY system where females have two of the same chromosome [XX] and males have two different ones [XY]).

a) The potential genotypes of the F1 are shown in attachment. This shows that all males will have dark wings (Ll) (all heterozygous) and all females will have light wings (l) (all will inherit l allele from father)

b) The potential genotypes of the F2 are shown in attachment. This shows that 50% of the males will have light wings (Ll), and 50% will have dark wings (ll). All of the females will have dark wings (L).