Bio 100 Plus Hour Assignment
Name
Lesson 2: Chromosomes and Karyotyping
Instructor
Lab Section
Introduction
Karyotyping is a technique that allows for the visualization and identification of human
metaphase chromosomes. This technique can be used to assess the “normalcy” of an individual’s
chromosomes and to assay for various genetic diseases such as Down’s syndrome and
Klinefelter’s syndrome. In this exercise you will go to websites, perform a karyotyping exercise
and view abnormal karyotypes and answer a series of questions.
Procedure:
1. If you are in the computer classroom, login to a CAL lab computer using ZULU/SIRS
2. Click on the Biology 100 Project (P) Course icon or go to the website:
http://www.biosbcc.net/bio100pcourse/index.htm
3. Choose the Chromosomes and Karyotyping lesson.
4. Click the button labeled Begin Lesson to start the lesson. Begin Lesson will take you to:
http://www.biology.arizona.edu/default.html
5. You should now be looking at a web page entitled “The Biology Project” at the
University of Arizona. Read the introduction and answer the following questions.
6. Find Activities in the left column.
7. Click on Karyotyping under Activities.
8. Read the introduction, and then begin the karyotyping exercise. Click Patient Histories
at the bottom of the page to begin the exercise.
9. You will complete a total of 3 karyotypes, and answer the following questions for each.
10. Click Complete Patient A’s Karyotype to begin the exercise for Patient A. You will
now be looking at a page entitled “Patient A’s Karyotype”. Follow the directions and
click the appropriate chromosome number to match the chromosome shown in the upper
left to its sister based on chromosome length and banding pattern. Do this for each
chromosome shown to complete the exercise and answer the questions below for
Patient A.
Questions #
• What notation would you use to characterize Patient A’s karyotype?
•
What diagnosis would you give patient A?
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Bio 100 Plus Hour Assignment
Lesson 2: Chromosomes and Karyotyping
11. At the bottom of the last page for Patient A, click Patient B to begin the exercise for
Patient B. You will now be looking at a page entitled “Patient B’s Karyotype”.
Complete this karyotype just as you did for Patient A and answer the questions below for
Patient B.
Questions #
• What notation would you use to characterize Patient B’s karyotype?
•
What diagnosis would you give patient B?
12. At the bottom of the last page for Patient B, click Patient C to begin the exercise for
Patient C. You will now be looking at a page entitled “Patient C’s Karyotype”.
Complete this karyotype just as you did for Patients A & B and answer the questions
below for Patient C.
Questions #
• What notation would you use to characterize Patient C’s karyotype?
•
What diagnosis would you give patient C?
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Bio 100 Plus Hour Assignment
Lesson 2: Chromosomes and Karyotyping
13. Once you have completed the karyotyping exercise at the University of Arizona site, then
go to the University of Washington website at:
http://www.pathology.washington.edu/galleries/Cytogallery/
14. You should now be looking at a web page entitled “Cytogenetics Gallery”
15. Enter the Gallery
16. In the left column, click What is a chromosome and read the description.
17. Now you will be asked to study some cytogenic abnormalities. In the left column click
Acquired then click Philadelphia Chromosome. Read the description and study the
karyotype of a person with Philadelphia Chromosome. The image of the karyotype is
enlarged when you click on it.
Questions #
• What is a translocation? (click on the word “translocation” in the text for a definition).
•
What is the fundamental chromosomal defect in a Philadelphia Chromosome?
•
What disease is associated with the Philadelphia Chromosome?
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Bio 100 Plus Hour Assignment
Lesson 2: Chromosomes and Karyotyping
18. In the left hand column, under Cytogenetic Abnormalities click on Constitutional then
click on Klinefelter’s Syndrome. Read about and study the Klinefelter’s karyotype.
Questions #
• How many chromosomes are found in the diploid cells of the individual whose karyotype
is shown for this example of Klinefelter’s Syndrome? Specifically which chromosomes
found in the cells of this person are the “extra copies” of chromosomes not normally found in
a human diploid cell.
•
Click on the underlined word gynecomastia. What is gynecomastia?
•
Click on the underlined word hypogonadism. What is hypogonadism?
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