1. Intro to Genetics

2. Terms to know before we start
Gene – A section of DNA that codes for a protein that determines a trait (physical characteristic)

3. Allele vs. Trait Allele – alternate forms of a gene
Ex. Trait – Eye color
Alleles – Blue, green, brown

4. You try it!!!!! This section of the chromosome codes for hair color.
What is the trait coded for by this gene?
What are the alleles for the gene?

5. Alleles can be dominant or recessive
Dominant – allele that is expressed when present
shown with _______________ letter
EX: B ~ allele for brown eyes
Recessive – allele that is hidden when dominant allele is present
shown with ________________ case letter
EX: b ~ allele for blue eyes

6. Homozygous vs. Heterozygous
Homozygous – two same alleles; purebred
EX. BB or bb
Heterozygous – two different alleles; hybrid or carrier
EX. Bb

7. Which chromosome set is heterozygous?

8. Genotype vs. Phenotype
Genotype: the two alleles an organism has for a trait
Phenotype: the physical appearance of the organism

9. Talk to a Partner: Determine the genotype and phenotype of each flower