Feather color in budgies is determined by two different genes, Y for pigment on the outside of the feather, and B for pigment on the inside of the feather. YYBB, YyBB, or YYBb is green; yyBB or yyBb is blue; YYbb or Yybb is yellow; and yybb is white. Two blue budgies were crossed. Over the years, they produced 22 offspring, five of which were white. What are the most likely genotypes for the two blue budgies?
A) yyBB and yyBB
B) yyBB and yyBb
C) yyBb and yyBb
D) yyBb and yybb

Question

Quizplus · Accepted Answer

Given that two blue budgies produced white offspring (yybb), both parents must carry the recessive b allele to pass it on to their offspring. Since they are blue (yyBB or yyBb), the only genotype that allows them to produce white offspring (yybb) through their combination is yyBb for both, as this genotype can provide both the y and b alleles needed for white offspring.

Feather Color in Budgies Is Determined by Two Different Genes