High school biology Assignments

A Chromosome Study

Background:

In this activity, you will create a karyotype from a page of mixed chromosomes. Karyotypes are created by matching homologous pairs and numbering them from largest to smallest. Abnormalities, such as extra or deleted chromosomes can then be diagnosed. Pictured chromosomes will be used for this model rather than real chromosomes, but the process is the same for real chromosomes extracted from cell or fetal samples.

{Check out https://www.sciencemusicvideos.com/ap-biology/module-18-meiosis/meiosis-tutorial-4-sex-determination-non-disjunction-and-human-chromosomal-variation/ to see what extracted chromosomes look like and how a karyotype is produced}

Three karyotypes will be created, the first two represent normal human karyotype of a male and a female, the second represents an abnormal karyotype. You will then compare and diagnose the abnormality present in the patient of the second karyotype.

Procedure:

1. Print out the sheets named Normal Boy, Normal Girl and Data Collection.

2. Print out one of the Set sheets. Each set is a different abnormality.

3. Examine the three sheets that you printed. Note that the sex chromosmes have been labeled for you as either X or Y chromosomes.

4. Using the Normal Boy sheet, cut out each chromosome (cut them as rectangles rather than trying to cut around the margin of each chromsome).

5. Prepare a karyotype of these chromosomes. A karyotype is a pattern of chromosomes grouped in homologous pairs and organized by size. Use size, location of the centromere, and banding marks to determine the pairs.

6. Use the Data Collection sheet to organize the pairs by size with the largest at 1 and the smallest at 22. The sex chromosomes will number 23.

7. Glue or tape the chromosome pairs in the correct order.

8. Using the Normal Girl sheet, cut out each chromosome.

9. Prepare a karyotype of these chromosomes using the Data Collection sheet to organize the pairs.

10. Glue or tape the chromosome pairs in the correct order.

11. Using the Set sheet that you chose, cut out each chromosome.

12. Prepare a karyotype of these chromosomes using the Data Collection sheet to organize the pairs.

13. Glue or tape the chromosome pairs in the correct order.

Analysis:

What was the letter on your set A?

1. What is the genetic disorder of this set? Why?

2. Research (using sources outside the textbook) the genetic disorder and describe some of the symptoms:

3. Cite your sources of information (at least one besides the textbook):

This Lab will be marked as follows:

Number	Score	Out Of
Set Letter	1	1
1	2	2
2	6	6
3	1	1
Total	10	10 Marks

BIOL200-30 Karyotype Lab Page 1 of 1