BIOL 110 Worksheet 5
1. Define the cell cycle and identify its two major divisions.
2. What is the difference in activities between phase G1, S and G2 stages of interphase?
3. How is the cell cycle is controlled by checkpoints and cyclins?
4. What does apoptosis accomplish?
5. What are cyclins and what is their function?
6. Explain how some much DNA can fit into the nucleus of eukaryotic cells
7. There have been few mutations in histone proteins during evolution. What have scientists determined this means?
8. What is chromatin and where is it located?
9. Explain the difference between haploid and diploid number of chromosomes and give an example of each type.
10. Explain the difference in function between a centrosome, centromere and a centriole.
11. What are sister chromatids and when are they first visible?
12. Identify the phases of mitosis with the associated action/event.
_____ telophase a. chromatin condensed and chromosomes visible
_____ anaphase b. spindle fibers disappear
_____ prophase c. centromeres in alignment
_____ metaphase d. sister chromatids separate
_____ late prophase e. kinetochores appear
13. What is the function of cytokinesis and in which mitotic phase does it commence and when does it end?
14. What is the function of mitosis?
15. What is the difference between reproductive and therapeutic cloning?
16. What is the ultimate cause of most types of cancer?
18. What are two genetic causes of cancer?
19. How can a telomerase mutation cause cancer?
20. Can binary fission and mitosis be considered to be forms of asexual reproduction? If so explain why.
21. What is meiosis, what type of cells does it produce and is it part of sexual or asexual reproduction?
22. What are homologous chromosomes?
23. When gametes unite, a zygote forms. Why does the zygote have paired chromosomes?
24. What is synapsis, when does it occur and what is the result called?
25. What happens following synapsis that results in gametes only having a diploid number of chromosomes?
26. How does crossing over and independent assortment generate genetic diversity in sexually reproducing organisms?
27. Why is genetic variation so important for species survival?
28. Explain the difference between euploidy and aneuploidy and give an example of the aneuploidy states.
29. Identify and describe the changes that can occur in chromosome structure.
30. Is a karyotype an effect means to determine if a person has trisomy 21? Explain.