Chap 16 Review PH
1. Define population.
2. Define gene pool.
3. If in a population 25% where AA and 30% were Aa, then what is the frequency of the A gene?
4. All the allele frequencies in a population add up to?
5. Does interbreeding usually change the gene frequencies in a gene pool?
6. Define mutation.
7. Two sources of genetic variation are:
8. Which source causes the most variation?
9. Gene shuffling includes what two processes?
10. Why do most organisms reproduce sexually as opposed to asexually?
11. Does gene-shuffling change the gene frequencies in a population?
12. If a pair of genes controlled for a trait and they showed a dominant-recessive relationship, how many phenotypes are possible?
13. What if they showed a non-dominance relationship?
14. Describe two ways a single gene trait differs from a polygenic trait.
15. What kind of graph would be used to represent a single gene trait?
16. What kind of graph would represent a polygenic trait?
17. Height in humans, birth weight in humans and beak size in Galapagos finches all show this kind of inheritance.
18. Does natural selection act directly on genes?
19. Describe the three different types of selection.
20. Define fitness.
21. When individuals from the middle of the bell curve are not fit this results in this kind of selection. If this happed to the Galapagos finches’ beaks, describe what would happen.
22. Gene frequencies changing due to chance is called:
23. What factor favors genetic drift?
24. What are the five factors that Hardy and Weinberg say must occur in order to keep the same gene frequencies (genetic equilibrium)?
25. Define founder’s effect. Relate to the Galapagos Islands.
26. How do Galapagos finches choose their mate?
27. Give an example of geographic isolation.
28. Define speciation.
29. What would happen if there were no reproductive isolation when speciation was occurring?
30. Give an example of temporal isolation.
31. How did ecological competition lead to directional selection in Darwin’s finches?
32. Polydactylism (having six fingers) is controlled by a dominant gene, then why is it unlikely a child would get this trait?
33. What would cause the gene frequency of a gene to decline over time?
34. Describe how a deck of playing cards can be used as an analogy to show genetic equilibrium and gene shuffling.
35. Give an example of how a point mutation can cause a change in a phenotype.
36. How can a point mutation NOT cause a change in a phenotype?
37. Directional and Disruptive selection, give one way in which they are similar and one way in which they are different.
38. Explain 3 ways in which the Hardy Weinberg assumptions maintain genetic equilibrium.
39. If a population got split into two places, give three reasons why speciation would occur.
40. How does ecological competition increase speciation?