1. Incomplete Dominance Codominance In a nutshell!

2. Review: Dominant/Recessive One allele is dominant over the other (capable of masking the recessive allele) PP = purple pp = white Pp = purple

3. Review Problem: Dominant/Recessive In pea plants, purple flowers (P) are dominant over white flowers (p) show the cross between two heterozygous plants. PpPp P p pp Pp PP - PP (1); Pp (2); pp (1) - ratio 1:2:1 - purple (3); white (1) - ratio 3:1 GENOTYPES: PHENOTYPES:

4. Snapdragons http://faculty.pnc.edu/pwilkin/incompdominance.jpg http://www.dobermann-review.com/info/genetics/mendels_genetic_laws/Gregor%20Mendel.jpg HUH?

5. Incomplete Dominance X R1R1 R2R2 F1F1 F2F2 R 2 R 2 does not produce pigment Heterozygote only produces ½ pigment of R 1 R 1 http://www.google.ca/images?hl=en&q=incoplete%20dominance&rlz=1W1SNNT_enCA397&um=1&ie=UTF-8&source=og&sa=N&tab=wi&biw=1345&bih=555

6. http://2.bp.blogspot.com/_uPFMFfHgGGg/SygBEtl5D1I/AAAAAAAAAKc/nylZiiL2k7s/s320/incomplete+dominance.jpg

7. Incomplete Dominance A third (new) phenotype appears in the heterozygous condition. Neither trait is completely dominant over the other, so a heterozygous plant is a mix. RR = redrr = whiteRr = pink

8. Problem: Incomplete Dominance Show the cross between a pink and a white flower. - Rr (2); rr (2) - ratio 1:1 - pink (2); white (2) - ratio 1:1 R r rrrr rrRr rr Rr GENOTYPES: PHENOTYPES:

9. Codominance The heterozygous condition, both alleles are expressed equally Lots of times, fur color in animals is this way. (think spotted or 2 colors)

10. CODOMINANCE The condition in which both alleles in a heterozygous organism are expressed. (Both are dominant together) BOTH alleles contribute to the phenotype. The two alleles don’t blend, but are rather both present in the offspring.

11. http://search.vadlo.com/b/q?rel=2&keys=Dominance+Incomplete+Dominance+Codominance+PPT Roan Horse

12. Roan Cattle Variegated Clover http://3.bp.blogspot.com/_zUPrgMM5tUg/SSVdrs59_uI/AAAAAAAAAA8/qJGjG2nZPhk/s200/codominance.GIF http://www.ccs.k12.in.us/chsteachers/BYost/Biology%20Notes/CH11notescoincompletedom_files/image004.jpg