1. 11.2 Applying Mendel’s Principles
Lesson Overview
11.2 Applying Mendel’s Principles

2. Terms to Know When Making Crosses
Punnett squares allow you to predict the genotype and phenotype of a genetic cross.
Homozygous = organisms that have two identical alleles.
Ex. - RR or rr
Heterozygous = organisms that have two different alleles.
Ex. - Rr

3. How To Make a Punnett Square
Determine the genotype of the parents.
Draw the Punnet Square and place the parents on either side.
Fill in the Punnet Square.
Record the genotype AND phenotype results.

4. How To Make a Punnett Square
Predict the phenotypic and genotypic ratios of a purple pea plant, RR
with a white pea plant, rr.
Genotypes
Phenotypes

5. How To Make a Punnett Square
Predict the phenotypic and genotypic ratios of two purple pea plants,
Rr.
Genotypes
Phenotypes

6. How To Make a Punnett Square
Predict the phenotypic and genotypic ratios of two purple pea plants.
One is heterozygous and the other is homozygous dominant.
Genotypes
Phenotypes

7. Mendel’s Principles
1) The principle of segregation = Alleles will separate during gamete formation.

8. Mendel’s Principles
2) The principle of independent assortment = Genes for different traits can separate independently of each other during gamete formation.