genotypes in offspring help?

Question

w have 2 independentlyassorting genes control the production of feature pigment, gene B codes fro anenzyme that is blue pigment, gene Y code fore enzyme of yellow pigment, the recessive allele of each gene codes for a non functional enzyme and no pigment is made, with blue and yellow pigment in their feathers are green, while with no pigment in their feathers are white
two green are mated, theiroffspring are green, blue, yellow, and white.
what are thegenotypes ofgreen parents, what is genotype of each four colors of offspring, what fraction of the total number offspring should be each color
plz help i really need your help, thanks in advance

Answer 1

You need to make yourself a key to make this problem clear.

B=blue
b=no pigment

Y=yellow
y=no pigment

B_Y_=green (BBYY or BbYY or BBYy or BbYy)
bbyy=white

Parents: B_Y_ x B_Y_ (both green where the underscore indicates the unknown allele which may be dominant or recessive)
Offspring: green, blue, yellow, white

Reason out the genotypes of the parents:
1. The white offspring must be bbyy, so the parents must each have a b and a y. Always look at the offspring with the recessive gene for the fastest route to the answer.
2. The parents are green, so the only possible genotype for the green parents is BbYy for each.

If parents are BbYy x BbYy, then gametes from each parent are BY, By, bY, by. Put one set of these four gametes on the left side of the Punnett square. Put another set of these four gametes (since the parents are alike) at the top of the Punnett square. Fill in the 16 boxes to see the genotypes of the offspring.

If you are familiar with dihybrid crosses, you know that crossing two heterozygotes makes a phenotype ratio of 9:3:3:1. In this case:
9/16 will be B_Y_ or green. (BBYY, BbYY, BBYy, BbYy)
3/16 will be B_yy or blue. (BByy, Bbyy)
3/16 will be bbY_ or yellow. (bbYY, bbYy)
1/16 will be bbyy or white. (only bbyy)

That was fun!