Question

statements about ball pythons
statement i: they are native to the forests and dry savannahs of africa.
statement ii: females are larger than males and can reach lengths of up to 2 m.
statement iii: they feed on small mammals and birds.
statement iv: most ball pythons have a patterned brown-and-black skin colour.
statement v: piebald is a recessive characteristic that causes white patches on the pythons skin.

question 2
which of the following rows describes the characteristics of the parents that together are expected to produce offspring that are only piebald?

\

$$\begin{tabular}{|c|l|l|} \\hline row & one parent & the other parent \\\\ \\hline \\bigcirc & brown-and-black skin colour & brown-and-black skin colour \\\\ \\hline \\bigcirc & brown-and-black skin colour & piebald \\\\ \\hline \\bigcirc & piebald & brown-and-black skin colour \\\\ \\hline \\bigcirc & piebald & piebald \\\\ \\hline \\end{tabular}$$

Explanation:

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<reasoning>

Identify the genetic nature of the trait

The problem states in Statement V that "Piebald is a recessive characteristic that causes white patches on the python's skin." Let us denote the recessive allele for piebald as \(p\) and the dominant allele for the patterned brown-and-black skin colour as \(P\).

Determine genotypes of the phenotypes

Since piebald is a recessive trait:

• A python with the piebald phenotype must have the homozygous recessive genotype: \(pp\).
• A python with the dominant brown-and-black skin colour phenotype can have either the homozygous dominant genotype \(PP\) or the heterozygous genotype \(Pp\).

Analyze the offspring requirement

The question asks which combination of parents is expected to produce offspring that are only piebald (100% piebald offspring).

• For an offspring to be piebald, it must inherit one recessive allele \(p\) from each parent, resulting in the genotype \(pp\).
• To guarantee that all offspring are piebald (\(pp\)), both parents must only be able to pass on the recessive allele \(p\). Therefore, both parents must have the genotype \(pp\).

Match genotypes to parent phenotypes

Since both parents must have the genotype \(pp\), their phenotypes must both be piebald:

• One Parent: Piebald (\(pp\))
• The Other Parent: Piebald (\(pp\))

Crossing two homozygous recessive individuals (\(pp \times pp\)) yields 100% homozygous recessive offspring (\(pp\)), which are all piebald. Any other combination involving a dominant brown-and-black parent (\(PP\) or \(Pp\)) could produce offspring with the dominant brown-and-black phenotype. This corresponds to the fourth row in the table.
</reasoning>

<answer>
<mcq-option>(Row 1) One Parent: Brown-and-black skin colour | The Other Parent: Brown-and-black skin colour</mcq-option>
<mcq-option>(Row 2) One Parent: Brown-and-black skin colour | The Other Parent: Piebald</mcq-option>
<mcq-option>(Row 3) One Parent: Piebald | The Other Parent: Brown-and-black skin colour</mcq-option>
<mcq-correct>(Row 4) One Parent: Piebald | The Other Parent: Piebald</mcq-correct>
</answer>

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Answer:

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<reasoning>

Identify the genetic nature of the trait

The problem states in Statement V that "Piebald is a recessive characteristic that causes white patches on the python's skin." Let us denote the recessive allele for piebald as \(p\) and the dominant allele for the patterned brown-and-black skin colour as \(P\).

Determine genotypes of the phenotypes

Since piebald is a recessive trait:

• A python with the piebald phenotype must have the homozygous recessive genotype: \(pp\).
• A python with the dominant brown-and-black skin colour phenotype can have either the homozygous dominant genotype \(PP\) or the heterozygous genotype \(Pp\).

Analyze the offspring requirement

The question asks which combination of parents is expected to produce offspring that are only piebald (100% piebald offspring).

• For an offspring to be piebald, it must inherit one recessive allele \(p\) from each parent, resulting in the genotype \(pp\).
• To guarantee that all offspring are piebald (\(pp\)), both parents must only be able to pass on the recessive allele \(p\). Therefore, both parents must have the genotype \(pp\).

Match genotypes to parent phenotypes

Since both parents must have the genotype \(pp\), their phenotypes must both be piebald:

• One Parent: Piebald (\(pp\))
• The Other Parent: Piebald (\(pp\))

Crossing two homozygous recessive individuals (\(pp \times pp\)) yields 100% homozygous recessive offspring (\(pp\)), which are all piebald. Any other combination involving a dominant brown-and-black parent (\(PP\) or \(Pp\)) could produce offspring with the dominant brown-and-black phenotype. This corresponds to the fourth row in the table.
</reasoning>

<answer>
<mcq-option>(Row 1) One Parent: Brown-and-black skin colour | The Other Parent: Brown-and-black skin colour</mcq-option>
<mcq-option>(Row 2) One Parent: Brown-and-black skin colour | The Other Parent: Piebald</mcq-option>
<mcq-option>(Row 3) One Parent: Piebald | The Other Parent: Brown-and-black skin colour</mcq-option>
<mcq-correct>(Row 4) One Parent: Piebald | The Other Parent: Piebald</mcq-correct>
</answer>

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