1. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings PowerPoint Lectures for Biology, Seventh Edition Neil Campbell and Jane Reece Lectures by Chris Romero Chapter 15 The Chromosomal Basis of Inheritance

2. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Concept 15.1: Where are genes located?  Located on chromosomes?

3. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Morgan’s Experimental Evidence: Scientific Inquiry Thomas Hunt Morgan – Chromosomes are the location of Mendel’s “heritable factors”

4. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Morgan’s Choice of Experimental Organism Morgan worked with Drosophila – Breed at a high rate – New generation every 2 weeks – 4 pairs of chromosomes

5. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Morgan observed: – Wild type = normal phenotypes common in the fly populations – Mutant phenotypes = abnormal/non-common Figure 15.3

6. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Morgan Experiment Mated: Female flies with red eyes (wild type) Male flies with white eyes (mutant)

7. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Morgan Experiment Mated: Female flies with red eyes (wild type) Male flies with white eyes (mutant) – What do you expect in the… – The F 1 generation = – The F 2 generation =

8. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings

9. What chromosomes differ in M vs. F?

10. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Morgan determined = white-eye mutant allele must be located on the X chromosome

11. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Morgan determined = white-eye mutant allele must be located on the X chromosome

12. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Morgan determined = white-eye mutant allele must be located on the X chromosome P F1

13. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Morgan determined = white-eye mutant allele must be located on the X chromosome P F1 F2

14. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Morgan determined = white-eye mutant allele must be located on the X chromosome

15. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Morgan’s Team

16. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Concept 15.2: Sex-linked genes exhibit unique patterns of inheritance

17. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Inheritance of Sex-Linked Genes Sex chromosomes – have genes unrelated to sex Gene located on either sex chromosome = sex-linked gene

18. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Disease caused by recessive alleles on X chromosome – Color blindness – Muscular dystrophy – Hemophilia

19. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Hemophilia

20. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Sex-linked genes – Follow specific patterns of inheritance

21. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Sex-linked genes – Follow specific patterns of inheritance

22. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings d. What % of offspring will be color blind g. What % of the males from this mating will be color blind?

23. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings X inactivation in Female Mammals Mammalian females – One of the two X chromosomes in each cell randomly inactivated during development – Heterozygote for gene on X?

24. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings X inactivation in Female Mammals Mammalian females – One of the two X chromosomes in each cell randomly inactivated during development – Heterozygote for gene on X?

25. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings X inactivation

26. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings X inactivation

27. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings X inactivation

28. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Concept 15.4: Alterations of chromosome Number or Structure  genetic disorders Number: Non-disjunction – Aneuploidy Trisomic, monosomic Structure (4):

29. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Non-disjunction

30. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Aneuploidy = Fertilization of gametes in which nondisjunction occurred 5 chromosome organism

31. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Aneuploidy Zygote is trisomic – 3 copies of a chromosome Ex: Down Syndrome

32. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Aneuploidy Zygote is trisomic – 3 copies of a chromosome Ex: XYY syndrome 1:1,000 men

33. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Aneuploidy Zygote is trisomic Ex: Klinefelter's Syndrome (XXY) syndrome

34. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Aneuploidy Zygote is trisomic Ex: Klinefelter's Syndrome (XXY) syndrome

35. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Aneuploidy Zygote is monosomic – 1 copy of a chromosome Ex: Turner syndrome = monosomy X

36. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Alterations of Chromosome Structure Breakage of a chromosome can lead to four types of changes in chromosome structure – Deletion – Duplication – Inversion – Translocation

37. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Deletion

38. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Deletion and Duplication

39. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Duplication

40. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Inversion

41. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Translocation

42. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Review! Ch. 15: Morgan’s Experiment: placed gene on chromosome Sex-linked inheritance patterns X Inactivation in female mammals Alterations in chromosome number or structure