1. 12/18/13 Objective: Who was Gregor Mendel and what were his contributions to genetics? Do Now: Why is there so much variation in sexually reproducing organisms?

2. Traits Traits: a variation of a particular character (ex: blue eyes or brown eyes)

3. Blending Hypothesis -A hypothesis to explain inheritance What color flower might you expect to get if you crossed a red and yellow flowered plant? -Blending of parental traits

4. Gregor Mendel -The first scientist to experiment with inheritance Genetics: the study of heredity

5. Particulate Hypothesis -Parents pass on to their offspring separate and distinct factors (genes) responsible for inherited traits

6. Pure-breeding -Mendel used true-breeding pea plants to experiment with genetics (purple flowers produce purple flowers)

7. Hybrids -The offspring of 2 different true breeding varieties (ex: a purple and a white flower)

8. Parental plants = p generation Hybrid offspring are called the: First filial = F1 generation When the F1 plants self-fertilize or fertilize each other they are the Second filial = F2 generation

9. Alleles: -alternative forms of genes (ex: purple flower or white flower) -- 2 alleles for the gene, one from each parent Homozygous: an individual with two of the SAME alleles Heterozygous: an individual with two DIFFERENT alleles

10. Dominant: A trait that will appear in the offspring if one parent contributes it, capital letter (B= Brown eyes) Recessive: a trait that must be contributed by both parents in order to appear in the offspring, lower case letter (b= blue eyes)

11. Crossing 2 parent plants that differ in only one character (trait)

12. Law of segregation: When a parent forms sex cells (egg or sperm), the parent’s gene pairs separate, so the sex cells carry only 1 allele for a particular trait Law of independent assortment: Each gene ppair for a trait is inherited independently of the gene pairs for all other traits. Law of Dominance: Each allele modifies the phenotype to some degree, producing a blended trait