1. Complex Patterns of Inheritance
A Day: 5/13/16
B Day: 5/16/16
3 Weeks Until Finals
Only 3 more lessons with new material!

2. Review
If a person is heterozygous for a trait, do they show the dominant or recessive phenotype?
Dominant

3. Complex Patterns
What kind of traits can you think of that seem to be “blends” of other traits?
Wavy hair looks like strait hair and curly hair blended
Pink flowers look like a blend of white and red flowers

4. Incomplete Dominance
Many traits result from alleles with a RANGE of dominance
In many cases both the dominant and recessive alleles will make proteins – the dominant protein is just more visible

5. Incomplete Dominance
In incomplete dominance, the heterozygous phenotype is a BLEND between the two homozygous phenotypes
When an allele is neither dominant nor recessive:
Uppercase letters with either subscripts or superscripts are used to represent different alleles

6. Codominance
Sometimes both alleles are expressed completely and there is no blending
Both traits are FULLY present
Ex: Spots on a horse

7. Polygenic Most traits are the result of MULTIPLE genes interacting
Skin color = 4 or more genes
Eye color = 3 or more genes

8. Eye Color: Polygenic Trait

9. Codominant or Incomplete Dominance?

10. Co or incomplete?
Co or incomplete?

11. Incomplete Dominance or Codominance?
COWDOMINANCE

12. Blood Types Blood type is a codominant trait:
1. Type A: Blood has antigen A
2. Type B: Blood has antigen B
3. Type AB: Blood has antigen A & B
4. Type O: Blood has no antigens
Which type best shows codominance?
Rh Factor: Either you have Rh or you don’t
A positive versus A negative

14. Blood Types

15. Videos!
Blood Type Vid #1: v=ttjn1jVACk8
Blood Type Vid #2: v=xfZhb6lmxjk

16. Blood Types – Self Quiz
In your own words, what makes the trait of blood types a codominant trait?
Both A and B antigens can be present on blood cells at the same time
The two traits do not blend together
The two traits are both present
How do you write a GENOTYPE for blood types?
Use superscripts to show different alleles
Give two examples of blood type genotypes
IAIA or IAIB

18. Answer #1
Check yo self!
Answer #2

19. Answers #3 & 4 YY

20. Answer #5

21. Hints for #9
The first step is to write out the GENOTYPE for the parents
Fred Fish’s Genotype: Yyrr
Olivia Fish’s Genotype: You figure this out on your own
Next create all gamete possibilities for EACH of the parents
Fred Fish’s gametes:
Yr, Yr, yr, & yr
Do Olivia’s gametes on your own
Then create a Punnett Square for this problem: You need to use more than one allele per gamete
Don’t just create a Punnett Square, answer the actual question 