Question

In cabbage butterflies, white wings (W) are dominant to yellow wings (w). A heterozygous butterfly mates with a butterfly that has yellow wings. Complete the Punnett square and then list the percentages of the expected genotypes for their offspring.

Answer 1

Answer:

(a)

$\begin{array}{ccc}{} & {W} & {w} & {w} & {Ww } & {ww } & {w} & { Ww} & {ww } \ \end{array}$

(b)

$White = 50\%$

$Yellow = 50\%$

Step-by-step explanation:

See attachment for initial punnet square

Solving (a): Complete the square

Initially, we have:

$\begin{array}{ccc}{} & {W} & {w} & {w} & { } & { } & {w} & { } & { } \ \end{array}$

To complete the square, we simply write the letter at the column and the letter at the row in each cell;

So, we have:

$\begin{array}{ccc}{} & {W} & {w} & {w} & {Ww } & {ww } & {w} & { Ww} & {ww } \ \end{array}$

Solving (b): Percentage of each

From the question, we understand that W are dominant to w.

So:

$Ww = White$

$ww = Yellow$

From (a) above

$Ww = 2$

$ww = 2$

$Total = 4$

So, the percentage of each is:

$White = \frac{Ww}{Total} * 100\%$

$White = \frac{2}{4} * 100\%$

$White = 0.5 * 100\%$

$White = 50\%$

$Yellow = 100\% - White$ --- Complement rule

$Yellow = 100\% - 50\%$

$Yellow = 50\%$