To determine the genotypes Mendel could have used for the cross in question, we need to consider the principles of Mendelian genetics. Mendel studied traits that were controlled by pairs of alleles, where one allele is dominant (represented by a capital letter) and the other is recessive (represented by a lowercase letter).
In this question, we are dealing with plants that are heterozygous for flower color. This means they have two different alleles for this trait – one dominant and one recessive.
Here are the genotypes given in the question:
1. P p: P p
2. p p′ p p
3. Pp
4. PP
Let's analyze each genotype:
1. P p: P p: This notation seems like an unconventional way to represent a genotype. Typically, we write the alleles side by side without any punctuation. So, we need to interpret this carefully. If we interpret it as representing two heterozygous plants, then it could be written as Pp and Pp.
2. p p′ p p: This notation looks unusual and not consistent with standard genetic representations. It seems to suggest multiple recessive alleles and some unclear notation involving p′. This is not a standard way to represent a heterozygous genotype, so we can exclude this option.
3. Pp: This represents a single heterozygous plant. However, for Mendel's cross involving two plants, we need two heterozygous plants, so this notation alone is incomplete.
4. PP: This represents a plant that is homozygous dominant. Since we are looking for heterozygous plants, this option does not apply.
Considering the provided answer:
Mendel could represent the cross between two heterozygous plants (Pp) using the genotype:
- Pp and Pp
Therefore, the possible answer appropriately representing Mendel's cross in this context is the first option, interpreted correctly as Pp and Pp.
