AP Biology
Chapter 18 Guided Reading Assignment
Name _________________________
1. How is the DNA arranged in the bacterial genome?
2. What is a plasmid?
3. Describe the process of binary fission.
4. Why do mutations make such a large contribution to bacterial genetic variation as
compared to humans?
5. What is the process of alteration of a bacterial cell’s genotype by the uptake of
naked, foreign DNA from the surrounding environment?
6. What famous experiment in the previous unit described this process?
7. Define transduction.
8. List the generalized steps of transduction.
9. What is the process of direct transfer of genetic material between two bacterial cells
that are temporarily joined?
10. What structure joins them?
11. What is special about the F plasmid?
12. What are R plasmids and why are they a problem to humans?
13. How does this relate to natural selection?
14. Define transposable elements.
15. What is an example of the benefit to bacteria of these transposable elements?
16. What is the key advantage of grouping genes of related function in to one
transcription unit?
17. What is this “switch” called?
18. Where is an operator positioned?
19. What does the operator control?
20. What is the name for the operator, promoter, and the genes they control?
21. What can happen if the trp operan is turned “on”?
22. What turns the “switch” off?
23. How does a repressor work?
24. What gene controls the making of the trp repressor protein?
25. How is the trp repressor protein an allosteric protein?
26. Why is the trp operon considered repressible?
27. What is the definition of an inducible operon?
28. What does the inducer do?
29. On the back of this sheet, explain the functioning of the lac operon: