11.1 The Work of Gregor Mendel Lesson Overview 11.1 The Work of Gregor Mendel

The Experiments of Gregor Mendel Genetics- scientific study of heredity; the delivery of characteristics from parent to offspring. The modern science of genetics was founded by an Austrian monk named Gregor Mendel. Mendel was in charge of the monastery garden. He developed the theory of inheritance before chromosomes were ever observed under the microscope!

Mendel’s Experiment’s Mendel studied 7 different characteristics of pea plants Characteristics- heritable feature that varies among individuals ex: flower color Trait- a specific characteristic of an individual, such as seed color or plant height, and may vary from one individual to another ex: purple Pea plants are true breeding or self- pollinating Hybridization: cross breeding of two contrasting varieties P generation: parental generation F1 generation: first filial generation F2…

The Role of Fertilization Hybrids: offspring of crosses between parents with different traits. Genes: factors that are passed from parent to offspring Alleles: different forms of a gene principle of dominance: some alleles are dominant and others are recessive An organism with at least one dominant allele for a particular form of a trait will exhibit that form of the trait. An organism with a recessive allele for a particular form of a trait will exhibit that form only when the dominant allele for the trait is not present.

The Law of Segregation When each parent, or F1 adult, produces gametes, the alleles for each gene segregate so that each gamete carries only one allele for each gene.

Genetic Vocabulary Homozygous-identical alleles for a characteristic ex: TT Heterozygous: two different alleles for a characteristic ex Tt Dominant: determines the expression Recessive: will only be seen if both alleles are recessive as in tt Genotype: genetic makeup (alleles) Phenotype: observable traits (what you see)