1. Punnet Squares
Continued…

2. Testcross Do a testcross!
For guinea pigs having a black coat is dominant.
How could you determine whether a black guinea pig is homozygous (BB) or heterozygous (Bb)?
Do a testcross!

3. Testcross
A testcross is when an individual of unknown genotype is crossed with a homozygous recessive individual
A testcross can determine if the genotype of test is homozygous or heterozygous!

4. Let’s Do The Squares! Homozygous dominant x homozygous recessive
Heterozygous x homozygous recessive

5. Incomplete Dominance
When the phenotype of a heterozygote is intermediate between the phenotypes determined by the dominant and recessive traits
Neither allele is completely dominant over the other allele

6. Incomplete Dominance Example: pink flowers can make red and white!
Pink (Rr) x Pink (Rr)

7. Codominanace
Occurs when both alleles for a gene are expressed in a heterozygous offspring.
Neither allele is dominant or recessive, nor do the alleles blend in the phenotype – they both show up
Example: human blood types

8. Blood Types
A0 B0 AB 00