Download Quiz 2 Q3 Review Sheet 3/8/11

Quiz 2 Q3 Review Sheet
Honors Biology
Quiz 2 will cover:
Chapter 11: Introduction, 11.1-11.11, 11.13, 11.15-11.19
21. Compare therapeutic cloning to reproductive cloning.
22. Compare embryonic stems cells to adult stem cells. Give an example of each. Which
are more useful to us and why?
23. If I contracted a virus that destroyed my motor neurons, explain how you would
generate new neurons that are genetically identical to me so that my immune system does
not reject them.
24. Explain how you would go about cloning yourself.
25. Compare stem cells to differentiated cells. How are they different? How does a
muscle cell differ from a pancreatic cell on the gene level? How are they the same?
26. What is gene expression?
27. “ESSAY” QUESTION: How is gene expression regulated in prokaryotes? What is an
operon? You need to be able to draw the lac operon in its entirety in both the on position
and the off position. Be able to explain a full cycle of regulation starting with the absence
of lactose in a bacterium in your mouth, then you drink a glass of milk resulting in the
presence of lactose, and then the absence again after the cell uses it up for cell resp and
biosynthesis. You will need to do this on the exam….draw and explain. Basically Figure
11.1B and explain it.
28. How does the trp operon differ from the lac operon? How are they the same?
29. Eukaryotic cells regulate gene expression individually (each gene) and regulation is
more complex partly to differentiation, which single-celled bacteria obviously don’t have
to worry about. Identify and explain the seven ways gene expression can be regulated in
eukaryotes. Try not to memorize them. Understand the ways as you think about
transcription and translation. They should be obvious. For example, you would always
regulate initiation of transcription and translation, never elongation and termination. You
want to stop it before it’s made. (Figure 11.11 is a great summary).
30. Explain how differentiated cells may retain their genetic potential under certain
conditions. Give two examples of differentiated cells in animals dedifferentiating (reverse
of differentiation).
31. Describe the advantages of cloning nonhuman mammals in basic research, agriculture
and medicine (section 11.4).
32. What is meant by X chromosome inactivation?
33. Describe the function of a transcription factor. What do we call the section of DNA
they bind to?
34. Compare enhancers to silencers (section 11.8).
35. Explain what is meant by signal transduction. Be able to explain how an extracellular
(outside the cell) signal that is unable to cross the membrane like a hydrophilic
polypeptide or protein is able to turn on or off genes inside the cell. Give an example of
such a signal.
36. Compare a proto-oncogene to an oncogene.
37. Compare proto-oncogenes to tumor suppressor genes. Give examples of each. What
do the proteins do that these genes code for? (Fig. 11.16A and 11.16B)
38. Why do scientists believe that both tumor suppressor alleles need to be mutated and
knocked out to get cancer while only one proto-oncogene needs to be mutated to an
oncogene in terms of signal transduction?
39. Explain how one gets cancer. How many mutations are required at minimum? Why?
Explain.
40. Read 11.18 and 11.19.
41. Describe what a carcinogen is and how does it relate to a mutagen? Take a brief look
at the table on page 227.
42. What is a mutation? List the various types of mutations discussed in class and discuss
how mutations arise in cells (spontaneous vs. induced, mutagens, carcinogens).
43. What is meant by the “reading frame” of a gene and how might a mutation alter the
reading frame?
44. Sickle cell anemia is caused by what kind of mutation? What about Tay Sachs?
45. ***Why are mutations so important to all species on Earth in terms of diversity and
evolution?