1. Incomplete Dominance  Neither allele is dominant over the other  Heterozygous offspring have a phenotype that is somewhere between the two.  Red + White = ___________

2. Incomplete Dominance  Homozygous red parent: RR crossed with Homozygous white parent: WW RR x WW yields heterozygous offspring RW that are pink  Red + White = ___________

3. Incomplete Dominance Circle the Heterozygous Flowers

4. Incomplete Dominance Circle the Homozygous Horses

5. Codominance  Both alleles contribute to the phenotype  Heterozygous offspring express both alleles Circle the word Codominance and underline the “Co” part of the word. Co refers to together, jointly or mutually.

6. Codominance X What Color Will the Offspring Be?

7. Codominance: A black chicken crossed with a white chicken results in a speckled chicken How is this type of inheritance different from incomplete dominance?

8. CODOMINANCE: ABO BLOOD TYPES  Blood type depends on the presence or absence of certain carbohydrates on the surface of red blood cells  3 alleles are possible: I A :Type A Blood I B :Type B Blood i : Type O Blood

9. ABO BLOOD TYPES  I A and I B are codominant to each other when they are paired.  i allele is recessive to both I A and I B If mom has type is homozygous for type A blood and dad is Homozygous for Type B blood, all of the offspring will have what blood Type?

10. Which blood type has no antigens?

11. Which blood type has both antigens?

12. Blood will reject cells that have foreign antigens. Type A would Reject type B and O would reject A and B and AB. Which blood type do You think would accept all the other blood types?

13. ABO Blood Groups Circle the square that shows type O blood.

14. ABO Blood Types  Blood typing is actually far more complicated than “A”, “B”, and “O”  ABO are the MAJOR antigens  There are also MINOR antigens Rh factor: “+” or “-” Rhesus macaqueRhesus macaque.

15. ABO Blood Types Circle your blood type if you know it. Put a star next to the most common blood type. Why is it surprising that type O is the most common blood type?

16. ABO Blood Types Laugh

17. ABO Blood Types The blood type that can receive blood from any other Blood type is known as the universal donor. Circle the blood type that is the universal donor. The universal receiver can accept blood from any Donor, put a square around the universal receiver.

18. ABO Blood Types  Why is it important to get the right blood type when getting a transfusion? Transfusion Reactions  Immune system (antibodies) will attack cells that have an antigen that the body doesn’t recognize as “self”

19. Transfusion Reaction

20. Multiple Alleles  More than 2 possible alleles exist in a population

21. Multiple Alleles  Coat color in rabbits: there are at least 4 different alleles  C = full color (dominant to all other alleles)  c (ch) = chinchilla  c (h) = himalayan  c = albino (recessive to all other alleles)

22. Full color rabbit

23. Chinchilla rabbit: partial defect in pigmentation

24. Himalayan rabbit: color in only certain parts of body

25. Albino rabbit: no color; recessive to all other alleles

26. Polygenic Traits  Traits that are produced by the interaction of more than one different genes

27. Polygenic Inheritance  For example: coat color in Labrador retrievers is a result of interaction of 2 different genes.

28. Polygenic Inheritance  Example: comb shape in chickens is a result of interaction between 2 different genes.

29. X-Linked Inheritance  Early 1900’s Thomas Morgan’s fruit fly studies Which Chromosome doe you think X-linked traits are found on?

30. X-Linked Inheritance

31.  More than 300 human traits are X- linked.  Most common X-linked recessive disorders: Hemophilia Red-green colorblindness Duchenne muscular dystrophy Adrenoleukodystrophy (seen in the movie Lorenzo’s Oil) How many X’s does a male have _____, how many does a female have _____ Who do you think is more likely to have an X-linked disorder? Male or Female.

32. BARR BODIES  Barr body is found only in females  It is a darkly staining area in the nucleus of a cell that represents an inactivated X chromosome  One X chromosome in each cell is randomly inactivated  How many active chromosomes are found in the cells of a human female?

33. Barr Body

34. Do you see the Barr body? Circle the Barr Body.

35. Barr Body: X inactivation  Calico cat Generally all females Have one X chromosome coding for for gold color, and one X chromosome coding for black color Color pattern shows how one X chromosome in each cell is randomly inactivated Why do you think Calico Cats are usually all female?

36. Calico Cat Color Inheritance

37. Calico Cat  There have been instances of male Calico cats found How could this happen?

38. Male Calico cat?  HINT: Male calico cats are sterile

39. Male Calico cat?  Answer: Male Calico cats have XXY chromosome configuration A Klinefelter’s cat? Yup, it happens.