Punnett Square interactive worksheet - Free Printable

Problem Explanation and Solution

The task involves using Punnett squares to predict the possible genotypes of offspring from given parents. Let's solve each problem step by step.

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#### Example 1: Eye Color
- Parents' Genotypes:
- Father: \( BB \) (dominant brown eyes)
- Mother: \( bb \) (recessive blue eyes)

- Punnett Square Setup:
- The father contributes either \( B \) or \( B \).
- The mother contributes either \( b \) or \( b \).

\[
\begin{array}{c|cc}
& B & B \\
\hline
b & Bb & Bb \\
b & Bb & Bb \\
\end{array}
\]

- Offspring Genotypes:
All offspring will have the genotype \( Bb \).

- Phenotype:
Since \( B \) is dominant, all offspring will have brown eyes.

Answer: All offspring will have brown eyes (\( Bb \)).

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#### Example 2: Hair Feature
- Parents' Genotypes:
- Father: \( Cc \) (curly hair, dominant)
- Mother: \( cc \) (straight hair, recessive)

- Punnett Square Setup:
- The father contributes either \( C \) or \( c \).
- The mother contributes either \( c \) or \( c \).

\[
\begin{array}{c|cc}
& C & c \\
\hline
c &Cc & cc \\
c &Cc & cc \\
\end{array}
\]

- Offspring Genotypes:
- Possible genotypes are \( Cc \) and \( cc \).

- Phenotype:
- \( Cc \): Curly hair (dominant)
- \( cc \): Straight hair (recessive)

Answer: The possible hair features of the child are:
- \( 50\% \) chance of curly hair (\( Cc \))
- \( 50\% \) chance of straight hair (\( cc \))

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#### Example 3: Petal Color in Flowers
- Parents' Genotypes:
- First flower: \( RR \) (red petal, dominant)
- Second flower: \( Rr \) (hybrid, red petal)

- Punnett Square Setup:
- The first flower contributes either \( R \) or \( R \).
- The second flower contributes either \( R \) or \( r \).

\[
\begin{array}{c|cc}
& R & r \\
\hline
R & RR & Rr \\
R & RR & Rr \\
\end{array}
\]

- Offspring Genotypes:
- Possible genotypes are \( RR \) and \( Rr \).

- Phenotype:
- Both \( RR \) and \( Rr \) result in red petals (since \( R \) is dominant).

Answer: All offspring will have red petals (\( RR \) or \( Rr \)).

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#### Example 4: Seed Pod Texture in Plants
- Parents' Genotypes:
- First plant: \( SS \) (smooth seed pod, dominant)
- Second plant: \( ss \) (wrinkled seed pod, recessive)

- Punnett Square Setup:
- The first plant contributes either \( S \) or \( S \).
- The second plant contributes either \( s \) or \( s \).

\[
\begin{array}{c|cc}
& S & S \\
\hline
s & Ss & Ss \\
s & Ss & Ss \\
\end{array}
\]

- Offspring Genotypes:
All offspring will have the genotype \( Ss \).

- Phenotype:
Since \( S \) is dominant, all offspring will have smooth seed pods.

Answer: All offspring will have smooth seed pods (\( Ss \)).

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Final Answers:

1. Eye Color: All offspring will have brown eyes (\( Bb \)).
\[
\boxed{\text{Brown eyes}}
\]

2. Hair Feature: The possible hair features are:
- \( 50\% \) chance of curly hair (\( Cc \))
- \( 50\% \) chance of straight hair (\( cc \))
\[
\boxed{\text{Curly hair (50\%), Straight hair (50\%)}}
\]

3. Petal Color in Flowers: All offspring will have red petals (\( RR \) or \( Rr \)).
\[
\boxed{\text{Red petals}}
\]

4. Seed Pod Texture in Plants: All offspring will have smooth seed pods (\( Ss \)).
\[
\boxed{\text{Smooth seed pods}}
\]