Name:________________________________Date:____________________
Period:_________________
Virtual Karyotyping Lab
Go to my website via the San Juan High School website. On the Biology page are the quick links to the
following websites.
Go to http://learn.genetics.utah.edu/content/begin/traits/ and click on “Make a Karyotype”.
1. What is a karyotype?
2. How does a karyotype help scientists?
3. How do scientists make a karyotype?
4. Try your hand at completing the karyotype. When you are finished,
signal your teacher to check it and stamp here: _______________
5. Does this person have the normal number of chromosomes? _____________
6. What can you tell about the sex of this person where the chromosomes came from?
Now go back to http://learn.genetics.utah.edu/content/begin/traits/ and click on “Using Karyotypes to
Predict Genetic Disorders”.
Watch the video on normal meiosis. Remember that meiosis is the formation of sex cells, or gametes.
7. How many chromosomes does a cell begin with during meiosis? ____________
8. After the two divisions during meiosis, how many chromosomes do the resulting egg or sperm have?
_______
Watch the video on fertilization.
9. An egg cell has ______ number of chromosomes and a sperm cell has ______.
10. When sperm and egg meet during fertilization, what do they form? ___________
11. How many chromosomes does it have? ________________
Chromosomal mutations can occur during meiosis if the chromosomes are not split in half properly. Watch
the video on abnormal meiosis to see how this can affect the resulting sex cells.
12. How many chromosomes do the new cells have in this example of abnormal meiosis? ____________
and __________________
Now watch the videos, “trisomy”, “monosomy” and “deletions” to see how the problems during meiosis
result in a baby with chromosomal mutations.
13. Did you watch the videos? __________
14. At the end of each video the zygotes formed did not have 46 chromosomes, but either more or less.
What kind of mutation is this when there are more or less chromosomes?
Name:________________________________Date:____________________
Period:_________________
Take the quiz and get a stamp ______________________
Click on http://www.biology.arizona.edu/human_bio/activities/karyotyping/karyotyping.html
15. How many times a year are karyotyping analysis done? _______________________________
16. What is the name of the dye they use to color the chromosomes so they can be seen?
______________________
Click “patient histories” and then complete patient A, B, and C’s karyotypes. Get a stamp after you
complete each karyotype.
In a patient with a normal number of chromosomes, each pair will have only two chromosomes. Having an extra or missing
chromosome usually renders a fetus inviable. In cases where the fetus lives to term, there are unique problems depending on which
chromosome is affected. Listed below are some syndromes caused by an abnormal number of chromosomes.
Diagnosis
Normal # of chromosomes
Klinefelter’s Syndrome
Down’s Syndrome
Trisomy 13 Syndrome
Patient
Stamp
Sex
Chromosomal Abnormality
Patient’s problems are due to something other than an
abnormal number of chromosomes
One or more extra sex chromosomes (XXX or XXY)
Extra chromosome 21
Extra chromosome 13
Chromosomes – normal or abnormal?
A
B
C
Write a summary of explaining what you have learned today:
Diagnosis