1. Solving Punnett Squares
If a round pea plant (AA) is crossed
with a wrinkled pea plant (aa), what
percent of the offspring will be:
• Round? Solve these
• Wrinkled?
If two heterozygous round pea
in your
plants are crossed, what percent of
the offspring will be:
• Round?
notebook.
• Wrinkled?
If a heterozygous round pea plant is crossed
with a homozygous wrinkled pea plant, what
percent of the offspring will be:
• Round?
• Wrinkled?

2. Practice
• Sponge Bob Genetics
• Glue in your notebook

3. Solving Punnett Squares
Predicting phenotype gets
more complicated when
you look at more than one
trait at a time.
Parents
Offspring

4. Solving Punnett Squares
Parents
Depending on how
chromosomes
independently
assort determines
genotype, and thus
phenotype, of the Offspring
resulting progeny
(offspring)

5. Solving Punnett Squares: page ___ of notebook
If a round, yellow pea plant
(AABB) is crossed with a
wrinkled, green pea plant
(aabb), what percent of the
offspring will be:
• Round and yellow?
• Round and green?
• Wrinkled and yellow?
• Wrinkled and green?

6. Practice
• Dihybrid Crosses handout (bunny rabbits).
Glue in your notebook.

7. Phenotypic Expression Varies
• Complete Dominance:
• Codominance Write this list,
• Incomplete Dominance
• Sex-Linked
then we will
• Polygenic Traits
describe each
one in detail.

8. Phenotypic Expression Varies
• Complete Dominance:
 Homozygous dominant genotype  dominant phenotype
 Heterozygous genotype  dominant phenotype
 Homozygous recessive genotype  recessive phenotype

9. Phenotypic Expression Varies
• Codominance
 Homozygous genotype  one phenotype
 Heterozygous genotype  both phenotypes

10. Phenotypic Expression Varies
• Codominance
 Homozygous genotype  one phenotype
 Heterozygous genotype  both phenotypes

11. Phenotypic Expression Varies
• Codominance
 Homozygous genotype  one phenotype
 Heterozygous genotype  both phenotypes
R R
W RW RW
W RW RW
R1 R1
R2 R1R2 R1R2
R2 R1R2 R1R2

12. Practice
• Intro to blood types (first 3 minutes good)
• Complete blood typing handout and glue in
your notebook.

13. Phenotypic Expression Varies
• Incomplete Dominance
 Homozygous genotype  one phenotype
 Heterozygous genotype  new phenotype

14. Phenotypic Expression Varies
• Incomplete Dominance
 Homozygous genotype  one phenotype
 Heterozygous genotype  new phenotype