1. Genetics Introduction and Vocabulary

2. History of Genetics Gregor Johann Mendel is the father of genetics
Modern genetics are based on Mendel’s explanations for the patterns of heredity in pea plants
Mendel’s experiments involved crossing different types of pea plants
Crossing means to mate or to breed

3. Why Pea Plants? Plants have contrasting traits Usually self-pollinates
Ex: Tall vs. short, or purple vs. white
Usually self-pollinates
Fertilizes itself rather than another plant
Fertilizing another plant is called cross-fertilization
Grows easily

4. Mendel’s First Experiment
- True breeding purple plants were crossed with true- breeding white plants. These plants are called the P generation.
The resulting plants are called the F1 generation. All plants in the F1 generation had purple flowers.
Two plants from the F1 generation were crossed to produce the F2 generation. ¾ of the plants in the F2 generation were purple and ¼ were white.
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5. Mendel’s Theories
Mendelian theory of heredity: Inheritance involves the passing of genes from parents to offspring.
Different traits result in different versions of genes. These different versions of genes are called alleles.
One allele comes from each parent
Ex: Dad gives you freckles and your mom does not

6. Mendel’s Theories
Law of segregation: During reproduction, the alleles that determine traits are separated into reproductive cells via meiosis and randomly reunite during fertilization

7. Mendel’s Theories
Law of independent assortment: Genes located on different chromosomes will be inherited independently of each other.