1. Mendel’s Work

2. Key Terms Traits = Physical Characteristics Heredity =
Passing of traits from parents to offspring.
Genetics =
Scientific study of heredity.

3. Mendel’s Peas

4. Mendel’s Experiments

5. Other Traits

6. Dominant and Recessive Alleles
Factors that control traits=
Genes
Different forms of a gene=
Alleles
An allele whose trait always shows up in the organism when the allele is present=
Dominant allele
An allele that is masked whenever the dominant allele is present=
Recessive allele

7. Understanding Mendel’s Crosses
P Generation
All plants were purebred
F1 Generation
All plants were Tall
All plants were hybrids-They had two different alleles for the trait.
F2 Generation
¾ were Tall ¼ were short
The short plants must have had two recessive alleles for the trait.

8. Using Symbols
Traits are represented by a capital letter of the Dominant form of the Trait.
For Example Tall Pea Plants have at least one dominant allele represented T.
Short Pea plants don’t have a dominant allele. If they had a dominant allele they wouldn’t be short. So they have two recessive alleles. tt

9. Mendel’s Contributions
1866 Mendel presented his findings.
Scientists did not understand importance.
Scientists thought he oversimplified work.
Mendel was discounted because he didn’t work at a university.
Mendel could not communicate work because no telephones or computers.
Mendel’s work was rediscovered 1900.
Many of his theories still stand today.

10. Mendel is Now Known as the Father of Genetics.