1. Variations to Inheritance Exceptions to Mendel’s Laws

2. Other Inheritance Patterns There are other ways that traits are inherited Scientist found out there are excepts to Mendel’s experiments 1)Incomplete Dominance 2)Codominance 3)X-Linked Traits (Sex-Linked) 4)Multiple Alleles 5)Polygenic Traits

3. Incomplete Dominance When an allele is not completely dominant over the other. Results in the offspring having a “blending” phenotype Example : Red Flowers X White Flowers _pink flowers

5. Codominance When both alleles Are expressed. Both are Dominant. Example – A cow with brown and white coat Think?????? - A pink plant and a white plant were crossed and the offspring exhibited codominance. What would the offspring look like?

7. X-Linked Traits Traits found on the sex chromosomes Some inheritance is autosomal – on the other 22 pairs chromosomes, while others are only found on the 23 pair chromosome, known as one the sex chromosome. Typically affect more males than females!

8. X-Linked Examples Color Blindness – unable to see certain colors such as red and green Hemophilia – disease where the blood is unable to clot.

10. Multiple Alleles More than two forms of alleles Our blood type is an example of a trait with more than 2 alleles Blood Types 1)A 2)B 3)O

11. Blood Groups An A blood type can have either AA allele or AO allele B Blood types will have BB or BO AB blood type will be AB An O blood type will be OO

12. Polygenic Traits When multiple alleles control one trait it is considered polygenic. Example such as skin color, height, eye color, or fingerprints are polygenic traits.