7 Pea Characteristics Pos. of Flowers (Axial or Terminal) Ht of Plant (Short or Tall) Pod Appearance(Smooth or Wrinkled) Pod Color (Green or Yellow) Seed Tex. (Round or Wrinkled) Seed Color (Green or Yellow) Seed Coat Color (Green or White)
His Mission was to determine whether or not there is any predictable pattern...
Pure Strain- Always produce offspring with the trait Self-Pollination Fertilization occurs within a single plant Cross-Pollination Fertilization occurs between 2 plants
P1- Parental Generation F1- First Filial, the offspring of the P1 generation F2- Second Filial, offspring when two F1s are crossed
One trait disappears in the F1 Generation?? It reappears in the F2 Generation as a 3:1 Ratio This happened with each set of traits His experiments help determine that genes occur in pairs Results
Principle of Dominance and Recessiveness Principle of Segregation – genes separate from each other during meiosis Principle of Independent Assortment –alleles separate independently of one another Mendel’s 3 Principals
Dominance and Recessivness One allele (form of a gene) in a pair may mask the effect of the other preventing it from having an effect. Dominant- The allele that masks the other factor Recessive- The allele that is masked, when the dominant allele is present.
oGene- A section of DNA that controls a particular trait oAllele- Alternate forms of a gene Capital Letter (D) for dominant Lower Case (d) for recessive
Genotype- Genetic Makeup of an organism Phenotype- Physical appearance of a gene Homozygous- Both alleles are the same (TT or tt) Heterozygous- Alleles are different (Tt)
Punnett Square A Punnett Square is a way of diagramming the probability of possible genetic outcomes. In other words, it’s a way of diagramming how offspring might come out genetically.