1. Exceptions to Mendelian Inheritance
1. Define and give examples of the 5 main exceptions to Mendel’s rules.

2. What Mendel said: One gene controlling one trait
That one gene has 2 forms
One gene is dominant and one gene is recessive

3. Incomplete Dominance: Occurs when the phenotype of the heterozygote is between those of the homozygotes.

4. Codominance: The heterozygote has the traits of both homozygotes.

5. Multiple Alleles: There are more than two alleles for a gene in a population.

6. Out of 100 donors . . . . . 84 donors are RH+ 38 are O+ 34 are A+
9 are B+
3 are AB+
16 donors are RH-
7 are O-
6 are A-
2 are B-
1 is AB-

7. Can be used sometimes to eliminate paternity

8. Polygenic inheritance: Occurs when MORE THAN ONE gene controls a single trait.

10. Sex linkage: determined by sex chromosomes.

11. Color blindness is sex linked

12. Baldness is sex-linked