1. CHAPTER 3 Independent Assortment of Genes CHAPTER 3 Independent Assortment of Genes Copyright 2008 © W H Freeman and Company

2. CHAPTER OUTLINE 3.1 Mendel’s law of independent assortment 3.2 Working with independent assortment 3.3 The chromosomal basis of independent assortment 3.4 Polygenic inheritance 3.5 Organelle genes: inheritance independent of the nucleus

3. Mendel’s law of independent assortment - different pairs assort independently in gamete formation

4. Figure 3-2 Round and wrinkled phenotypes

5. Figure 3-3 Mendel’s breeding program that produced a 9 : 3 : 3 : 1 ratio

6. Figure 3-4 Punnett square illustrating the genotypes underlying a 9 : 3 : 3 : 1 ratio

7. Working with independent assortment

8. Table 3-1 Generally, a hypothesis is rejected as false if there is a probability of less than 5% of observing a deviation from expectations at least as large as the one actually observed. In other words, there is a less than 5% probability that the deviation between the observed and expected values is because of chance.

9. The chromosomal basis of independent assortment

10. Figure 3-7 Different chromosomes segregate independently

11. Figure 3-8 Independent assortment of chromosomes at meiosis explains Mendel’s ratio

12. Figure 3-8 part 1 Independent assortment of chromosomes at meiosis explains Mendel’s ratio

13. Figure 3-8 part 2 Independent assortment of chromosomes at meiosis explains Mendel’s ratio

14. Figure 3-9 Stages of a Neurospora cross

15. Figure 3-10a The linear meiosis of Neurospora

16. Figure 3-10b The linear meiosis of Neurospora

17. Figure 3-11 Recombinants are meiotic output different from meiotic input

18. Figure 3-12 In diploids, recombinants are best detected in a testcross

19. Figure 3-13 Independent assortment produces 50 percent recombinants

20. Polygenic inheritance

21. Figure 3-14 Continuous variation in a natural population

22. Figure 3-15 Polygenes in progeny of a dihybrid self

23. Figure 3-16 Histogram of polygenes from a dihybrid self

24. Figure 3-17 Histogram of polygenes from a trihybrid self

25. Organelle genes: inheritance independent of the nucleus

26. Figure 3-18 Cell showing nucleoids within mitochondria

27. Figure 3-19 Organelle genomes

28. Figure 3-20a Maternal inheritance of mitochondrial mutant phenotype poky

29. Figure 3-20b Maternal inheritance of mitochondrial mutant phenotype poky

30. Figure 3-21 Variegated leaves caused by a mutation in cpDNA

31. Figure 3-22 Crosses using flowers from a variegated plant

32. Figure 3-23 Model for cytoplasmic segregation

33. Figure 3-24 Sites of mtDNA mutations in certain human diseases

34. Figure 3-25 Pedigree of a mitochondrial disease