A Monk’s Life

• Gregor Mendel was a Austrian monk in charge of tending the garden.

• He Studied the common garden pea to become. . .

THE FATHER OF GENETICS!!!!

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 traitSelf-Pollination

Fertilization occurs within a single plant

Cross-PollinationFertilization 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.