Experiment 3: The Importance of Cell Cycle ControlSome environmental factors can cause genetic mutations that result in a lack of
proper cell cycle control (mitosis). When this happens, the possibility for
uncontrolled cell growth occurs. In some instances, uncontrolled growth can lead
to tumors, which are often associated with cancer, or other biological diseases.
In this experiment, you will review some of the karyotypic differences that can be
observed when comparing normal, controlled cell growth and abnormal,
uncontrolled cell growth. A karyotype is an image of the complete set of diploid
chromosomes in a single cell.
Materials
*Computer Access
*Internet Access
*You Must Provide
Procedure
1. Begin by constructing a hypothesis to explain what differences you might
observe when comparing the karyotypes of human cells with normal cell
cycle control versus cancerous cells (which experience abnormal, or a
lack of, cell cycle control). Record your hypothesis.
Note: Be sure to include what you expect to observe, and why you think
you will observe these features. Think about what you know about
cancerous cell growth to help construct this information.
2. Go online to find some images of abnormal karyotypes, and normal
karyotypes. The best results will come from search terms such as
“abnormal karyotype,” “HeLa cells,” “normal karyotype,” “abnormal
chromosomes,” etc. Be sure to use dependable resources that have been
peer-reviewed.
©eScience Labs, 2016
3. Identify at least five abnormalities in the abnormal images. Then, list and
draw each image in the Data section at the end of this experiment. Do
these abnormalities agree with your original hypothesis?
Hint: It may be helpful to count the number of chromosomes, count the
number of pairs, compare the sizes of homologous chromosomes, look for
any missing or additional genetic markers/flags, etc.
Data
1.
2.
3.
4.
5.
Post-Lab Questions
1. Record your hypothesis from Step 1 in the Procedure section here.
2. What do your results indicate about cell cycle control?
©eScience Labs, 2016
3. Suppose a person developed a mutation in a somatic cell which
diminishes the performance of the body’s natural cell cycle control
proteins. This mutation resulted in cancer, but was effectively treated with
a cocktail of cancer-fighting techniques. Is it possible for this person’s
future children to inherit this cancer-causing mutation? Be specific when
you explain why or why not.
©eScience Labs, 2016