1. Heredity!!! Passing on traits from parents to offspring

2. Gregor Mendel Austrian Monk Austrian Monk “Father of Genetics” “Father of Genetics” 1866 Published Findings 1866 Published Findings

3. Mendel Sez Genes inherited from parents. 1 gene from mom, 1 gene from dad Genes inherited from parents. 1 gene from mom, 1 gene from dad There are alternate versions of genes (all genes are not exactly the same). These are called alleles. There are alternate versions of genes (all genes are not exactly the same). These are called alleles. If an organism has two alleles that are different only 1 is shown If an organism has two alleles that are different only 1 is shown Gametes (sex cells) only carry one allele, not both Gametes (sex cells) only carry one allele, not both NO BLENDING NO BLENDING

6. Alleles Alleles are different types of the same gene Alleles are different types of the same gene Always have 2 alleles for each gene in an individual Always have 2 alleles for each gene in an individual Alleles can be recessive or dominant Alleles can be recessive or dominant Recessive alleles do not show the trait in the presence of a dominant allele Recessive alleles do not show the trait in the presence of a dominant allele Dominant alleles ALWAYS show the trait Dominant alleles ALWAYS show the trait Earlobes: Free ear lobes (dominant trait) Attached ear lobes (recessive trait) Free Attached

7. Phenotype The physical appearance of the trait. The appearance of an allele. The physical appearance of the trait. The appearance of an allele. Gold Color Allele White Color Allele Black Color Allele Yellow Color Allele

8. Genotype The actual alleles: WW or Ww or ww The actual alleles: WW or Ww or ww W is purple allele and dominant W is purple allele and dominant w is white allele and recessive w is white allele and recessive This plant could be WW or Ww This plant could only be ww

9. Allele Combinations Cells have 2 alleles of for each gene Cells have 2 alleles of for each gene Heterozygous: both alleles are different Heterozygous: both alleles are different Ww Ww Homozygous: both alleles are the same Homozygous: both alleles are the same WW or ww WW or ww Special Note: In order to display a recessive characteristic, individual must be homozygous recessive.

10. Generations Parents: P Generation Parents: P Generation First Offspring Generation: F 1 First Offspring Generation: F 1 Second Offspring Generation: F 2 Second Offspring Generation: F 2 P Generation F 2 Generation F 1 Generation

11. Laws of Heredity Law of Segregation Law of Segregation 2 Alleles segregate (separate) when gametes (sex cells) are formed. Remember meiosis… 2 Alleles segregate (separate) when gametes (sex cells) are formed. Remember meiosis… Law of Independent Assortment Law of Independent Assortment Alleles of different genes separate independently of each other Alleles of different genes separate independently of each other