Question

what are the gametes for bbdd? (use foil) options:

1. b, d, d

bd, bd, bd, bd
bd, bd, bd, bd
bd, bd, bd, bd

Explanation:

Step1: Define FOIL for gametes

FOIL = First, Outer, Inner, Last. For genotype $BbDd$, the allele pairs are $(B,b)$ and $(D,d)$.

Step2: Apply First

Combine first alleles of each pair: $B + D = BD$

Step3: Apply Outer

Combine outer alleles of each pair: $B + d = Bd$

Step4: Apply Inner

Combine inner alleles of each pair: $b + D = bD$

Step5: Apply Last

Combine last alleles of each pair: $b + d = bd$

Step6: Compile all gametes

List all unique gametes from steps 2-5.

Answer:

BD, bD, Bd, bd