For a type of cat, short whiskers are dominant [tex]\((S)\)[/tex] and long whiskers are recessive [tex]\((s)\)[/tex]. The Punnett square below shows a cross between two cats. What is the phenotype ratio for this cross?

\begin{tabular}{|c|c|c|}
\hline
& s & s \\
\hline
s & Ss & Ss \\
\hline
s & Ss & ss \\
\hline
\end{tabular}

A. 2 short, 2 long

B. 0 short, 4 long

C. 3 short, 1 long

D. 4 short, 0 long



Answer :

To determine the phenotype ratio for the cross given in the Punnett square, let's analyze the genetic outcomes listed:

[tex]\[ \begin{array}{|c|c|c|} \hline & s & s \\ \hline s & SS & Ss \\ \hline s & Ss & ss \\ \hline \end{array} \][/tex]

Here are the possible combinations for the offspring:
1. SS
2. Ss
3. Ss
4. ss

Let's identify the phenotypes for each genotype:
- SS: Homogeneous dominant, resulting in short whiskers.
- Ss: Heterogeneous, resulting in short whiskers.
- Ss: Another heterogeneous, resulting in short whiskers.
- ss: Homogeneous recessive, resulting in long whiskers.

Now count the number of each phenotype:
- Short whiskers (SS, Ss, Ss): 3 times.
- Long whiskers (ss): 1 time.

Thus, the phenotype ratio for this cross is as follows:
- 3 short whiskers : 1 long whisker

So the correct answer is:
C. 3 short, 1 long