1. Ch 15 pictures

2. Is your clicker # on this list? 14, 23, 29, 36, 40, 53, 69, 74, 75, 92, 93, 99, 100. If so, let me know your name so I can give you credit for attending class. Thanks! Dr. H

3. Today: Announcements

4. Historical Perspective 1860’s Mendel proposed that discrete factors segregated and independently assorted during gamete formation. Genetics Cytology 1875: Cytologists worked out the process of mitosis. 1890: Cytologists worked out the process of meiosis. 1900: Three botonists (Correns, deVries and von Seysenegg) independently rediscovered Mendel’s Principles 20 years after his death. Early 1902: Walter Sutton, Theodor Boveri and others hypothesized that genes are on chromosomes.

5. Thomas Hunt Morgan

6. Drosophila melanogaster

7. Morgan’s Symbols Wild Type Mutant

8. Morgan’s Symbols (homozygote recessive) (heterozygote) White Eyes = w Red Eyes = w+ w+ww+w ww

9. Morgan’s Symbols Curly Wings

10. Question 15.1

11. Sex-linkage in Drosophila

12. First Filial Generation of Fruit Flies Male Female w+ (X chromosome) w+ w w (X chromosome) Y chromosome w+ (X chromosome) w+ w w+ y F1 Phenotype All red Eyes Genotype Females= w+w Males= w+y Parentals

13. Second Filial Generation of Fruit Flies Male Female w+ (X chromosome) w+ w w+ (X chromosome) Y chromosome w (X chromosome) w+ w+ w+ y w y F2 3/4 red eyes 1/4 white eyes Only males had white eyes F1 generation

14. Y Chromosome in Humans

15. Recessive Disorders Red-green colorblindness Duchenne muscular Dystrophy (muscles break down and are eventually lost) Hemophilia (missing Blood clotting factor)

16. Question 15.2

17. Colorblind Inheritance in Females X cb Mother Father X cb Y

18. Alterations in Chromosomes

19. Fig 15.12 Meiotic Nondisjunction

20. One copy of Chromosome #1 No chromosome #1 Fertilization One Chromosome #1 X Embryonic Lethal All others paired

21. Monosomy XO

22. Trisomy XXY

23. Trisomy Chromosome 21 (not in a sex chromosome)

24. Fig 15.14: Alterations in Chromosome Structure

25. Chromosome 5 deletion

26. Question 15.3

27. X inactivation and the tortoiseshell cat

28. Figure 15.9 Some chromosomal systems of sex determination

29. Question 15.4