Question

if a white - flowered pea plant (ww) is crossed with a heterozygous purple - flowered plant (ww), what will their offspring look like?
multiple choice
one - quarter of the offspring will be purple - flowered homozygotes, half will be purple - flowered heterozygotes, and one - quarter will be white - flowered
all of the offspring will be white - flowered homozygotes
half the offspring will be purple - flowered heterozygotes, and half will be white - flowered
all of the offspring will be purple - flowered heterozygotes

Explanation:

Step1: Determine gametes

The white - flowered plant (ww) can only produce gametes with the allele 'w'. The heterozygous purple - flowered plant (Ww) can produce gametes with alleles 'W' and 'w'.

Step2: Use Punnett square

	W	w
w	Ww	ww

From the Punnett square, we can see that half of the offspring have the genotype Ww (purple - flowered heterozygotes) and half have the genotype ww (white - flowered).

Answer:

Half the offspring will be purple - flowered heterozygotes, and half will be white - flowered.