Question

genetic review
in the dihybrid cross, brown hair (h) is dominant over blonde hair (h) and green eyes (g) is dominant blue eyes (g).

	hg	hg	hg	hg
hg	hhgg	hhgg	hhgg	hhgg
hg	hhgg	hhgg	hhgg	hhgg
hg	hhgg	hhgg	hhgg	hhgg

what fraction of the offspring are blonde and blue eyes?

• 1/16
• 9/16
• 4/16
• 2/16

Explanation:

Step1: Determine the genotype for blonde and blue eyes

Blonde hair is recessive (\(h\)) and blue eyes are recessive (\(g\)). The genotype for blonde hair and blue eyes is \(hhgg\).

Step2: Count the number of \(hhgg\) genotypes in the Punnett - square

Looking at the Punnett - square, we can see that there is \(1\) cell with the genotype \(hhgg\).

Step3: Calculate the total number of offspring

The Punnett - square has \(4\times4 = 16\) cells (representing all possible offspring genotypes).

Answer:

\(\frac{1}{16}\)