Prelecture Preparation to discuss mitosis and cancer:
Name- _________________________________________
Directions- Using your lecture notes, book and key from the cell communication lecture we went over
in lab last week, answer the following questions.
1) Cells elaborate extracellular signals (e.g. cytokines and steroids) to communicate with each
other. In general extracellular signaling molecules fall into two classes, lipophilic which can cross
the cell membrane (e.g. steroids) and non-lipophilic which can’t cross the cell membrane on
their own (e.g. proteins like cytokines). So when cell encounter an extracellular signaling
molecule that is non- lipophilic the signal must somehow cross the cell membrane. In general,
how do cells do that? Be sure to include details about how the cell “detects” the extracellular
signal and how the signal is transduced (i.e. moved across) across the cell membrane.
2) When the signal above is detected several intracellular signals must be initiated.
a. In general, what term is used to describe this intracellular signaling process.
b. What is the purpose of this signaling process?
c.
3) What are transcription factors and how do they relate to the ideas you outlined in #1 and #2?
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4) In previous lectures, we discussed how cells (like intestinal epithelial cells) physically interact
with each other and their surroundings to form tissues and to have specific functions. How do
intestinal epithelial cells accomplish this? That is what are the specific structures used for this?
Drawing a picture would be helpful.
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Lecture Questions
Mitosis and Cancer
Name- _________________________________________
Directions- Using your lecture notes and book, answer the following questions.
1) Diagram the pie chart used to indicate the fraction of time a normal cell is found in the different
phases of cell cycle.
a. Indicate on the pie chart where the cell checks itself prior to cell division in 3 places.
i. What in general is the cell checking?
ii. What term is used to refer to these places on the pie chart collectively?
iii. What is checked at these 3 places?
iv. What are the two types of proteins that regulate the cell as it moves through
this process?
v. How are the two proteins you described in the above question regulated?
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2) Using a pie chart, show how the cell cycle in cancer cells differs from normal cells in general?
3) As we discussed previously, the enzyme used to replicate (i.e. copy) DNA and when in cell cycle
does the process of replication occur. Describe this below?
4) What is the difference between an oncogene and a proto-oncogene?
5) What is the Multiple-Hit Hypothesis?
6) What is metastasis?
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Lecture Questions
Meiosis and Genetic Variation During Sexual Reproduction
1) From the point of view of the DNA in the cell, diagram the stages of meiosis
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2) Besides DNA polymerase missing its mistakes and thus causing mutations, describe the three
ways eukaryotic organisms generate genetic variability through sexual reproduction. Be sure to
explain each fully. Diagrams may be useful to explain the ideas.
3) Describe how meiosis can accidentally lead to gametes (eggs and sperm) that have more than
the haploid number of chromosomes (i.e. one copy a homologous chromosome).
4) Chromosonal abnormalities come in several varieties, based on what we described in lecture,
what are these variations?
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5) From the point of what happens to the DNA in the cell only, describe how meiosis and mitosis
differ from each other.
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