Download Cell Cycle

BSCS
Unit 2, Chapter 8
The Cell Cycle
1. In the photo on p. 212, these cells are undergoing
processes in the cell cycle. What are the structures that you
can see that appear to be bluish-black? Why do they appear
different in different cells?
2. What are the 2 basic stages of the cell cycle?
3. What are the 3 stages of interphase?
4. What is a restriction point and what is its significance in
the cell cycle?
5. What is happening to the cell in G0?
6. What is mitosis? What are its 4 stages? What is the result
of mitosis?
7. How does the importance of cell division differ in
unicellular and multicellular eukaryotes?
8. What determines whether a cell stays in interphase or
divides?
9. Label the diagram of mitosis below.
10. What has happened to the DNA in the first step?
11. Study the diagram below. Describe how DNA replicates
itself.
12. What are the enzymes involved in this process?
13. In the space below, draw a typical chromosome that you
might expect to see in metaphase. Label the chromatids
and the centromere.
14. What is meant by leading strand and lagging strand?
What is meant by complementary base pairing?
15. In what direction (3’-5’ or 5’-3’) does replication take
place? What does this mean?
16. What is a nucleosome? What is its relationship to a
histone?
17. How does the DNA molecule repair itself?
18. What are the three different roles of DNA polymerase in
DNA replication?
19. Explain how DNA synthesis can proceed in both
directions from a replication origin, even though DNA
polymerase can synthesize DNA only in one direction.
20. How are histones involved in gene expression?
21. Study the DNA molecule below. What do you notice
about the complementary nitrogen bases?
22. What forms the backbone of the DNA molecule?
23. What forms the “rungs” of the ladder of DNA? What
holds the nitrogen bases together?
24. In the space below, draw a simple diagram of bacterial
cell division, a process known as binary fission. Explain the
process.
25. How are bacteria able to replicate their one long loop of
DNA?
26. What are the current theories regarding the evolution of
mitosis?
27. What controls the cell cycle?
28. Read the Focus On section. Describe how a cell
becomes cancerous.
29. Explain why neither cyclins nor kinases alone can cause
a cell to progress through the cell cycle.
30. How do controls on the cell cycle protect multicellular
organisms from accumulating large numbers of damaged or
defective cells?
31. What is the difference between a cancerous tumor and
metastasis?
32. What are the functions of tumor-suppressor genes and
proto-oncogenes in noncancerous cells?