Partner Names: ______________________________________ _______________________________________ Period: ___________
Date: _________________________________
Human Karyotyping Lab #
Background: Occasionally chromosomal material is lost or rearranged during the formation of gametes or during cell
division of the early embryo. Such changes, primarily the result of nondisjunction or translocation, are so severe that the
pregnancy ends in miscarriage – or fertilization does not occur at all. It is estimated that one in 156 live births have some
kind of chromosomal abnormality. Some of the abnormalities associated with chromosome structure and number can be
detected by a test called a karyotype. A karyotype can show prospective parents whether they have certain
abnormalities that could be passed on to their offspring, or it may be used to learn the cause of a child’s disability.
Karyotypes can also reveal the gender of a fetus or test for certain defects through examination of cells from uterine fluid
– a procedure called amniocentesis – or through sampling of placental membranes. Over 400,000 karyotype analyses
are performed each year in the U.S. and Canada. To create a karyotype, chromosomes from a cell are stained and
photographed. The photograph is enlarged and cut up into individual chromosomes. The homologous pairs are identified
and arranged in order by size (with the exception of the sex chromosomes; these appear last). These tests are typically
done on a sample of blood, although any body cell could be used. The cell must be undergoing mitosis – preferably in
metaphase – so that the chromosomes are replicated, condensed, and visible under a microscope.
(adapted from: http://www.slic.wsu.edu/bios/biol107/107Karyotypesp05.pdf)
Purpose: The purpose of this laboratory experience is:
-understand what a karyotype is and how it is performed.
-understand the reason for performing a karyotype, especially for those with a higher risk of genetic defect in
their lineage.
-to determine what genetic defect is present in a chromosome sample.
-to investigate a variety of genetic disorders that commonly occur and are studied in biology classes.
Materials: The following materials are needed to perform this laboratory experience:
Scissors
tape
ruler
small envelope
Procedure: The following procedure is utilized to perform this laboratory experience:
1. Complete your assigned karyotypes: One normal male, One normal female, and five different disorders .
2. Working slowly and carefully, using scissors cut out the chromosome on one page labeled “1” and find its’ EXACT match
elsewhere on the page (it will not be numbered). Cut out this chromosome and tape BOTH chromosomes side by side on a “data
page” that has the heading filled out.
3. Continue this procedure until you have matched all chromosomes and taped each of them in the corresponding place on the data
page.
4. If you are caught short of time, use the coin envelope to store any chromosomes you may have clipped out and not matched. DO
NOT CUT OUT ALL CHROMOSOMES AND THEN ATTEMPT TO MATCH THEM!!! Cut out only one at a time or you will lose
chromosomes.
5. In the event that you have an extra chromosome, DO NOT THROW IT OUT! It is the chromosome that causes your
mutation/disorder and you must match it correctly.
6. Once your chromosomes are all cut out and included in the karyotypes, answer the questions and complete the lab report.
Define the following terms, (you may need to research some terms):
Somatic Cell-__________________________________________________________________________________
Karyotype-____________________________________________________________________________________
Diploid chromosome number-_____________________________________________________________________
Haploid chromosome number-____________________________________________________________________
Autosome-____________________________________________________________________________________
Sex Chromosome-______________________________________________________________________________
Nondisjunction-________________________________________________________________________________
Trisomy -_____________________________________________________________________________________
Monosomy -___________________________________________________________________________________
Questions: Answer the following questions before turning in your lab.
1. Place a check mark (√) next to the karyotypes completed by your group.
a.
b.
c.
d.
e.
f.
g.
h.
_______Set A
_______Set B
_______Set C
_______Set D
_______Set E
_______Set F
_______Normal Male
_______Normal Female
2. What were the sexes of:
a. Set A _____________________ - _______________________________
b. Set B _____________________- _______________________________
c. Set C _____________________- _______________________________
d. Set D _____________________- _______________________________
e. Set E _____________________- _______________________________
f.
Set F _____________________- _______________________________
3. Which chromosome is the single most significant factor that determines a male’s sex? ________________
4. Answer the following questions pertaining to each of the karyotypes. YOU WILL NEED TO RESEARCH THE
DISORDERS TO ANSWER SOME QUESTIONS.
a. Normal Male
i. ___________How many TOTAL chromosomes?
ii. ___________How many chromosomes are present in each cell of the male?
iii. ___________How many autosomes are present in a normal male?
iv. ___________How many sex chromosomes are present in a normal male?
v. ___________What are the sex chromosomes in a normal male?
b. Normal Female
i. ___________How many TOTAL chromosomes?
ii. ___________How many chromosomes are present in each cell of the female?
iii. ___________How many autosomes are present in a normal female?
iv. ___________How many sex chromosomes are present in a normal female?
v. ___________What are the sex chromosomes in a normal female?
c. Set A
i. ___________How many TOTAL chromosomes?
ii. ___________How many chromosomes are present in each cell of the human?
iii. ___________How many autosomes are present in this karyotype?
iv. ___________How many sex chromosomes are present in this karyotype?
v. ___________Is this karyotype that of a male or female?
vi. Which type of disorder is depicted in this karyotype? Circle one:
Autosomal
or
Sex-Linked
vii. What is the name of this disorder?
________________________________________________
viii. List five characteristics of this disorder.
1. _____________________________________________________
2. _____________________________________________________
3. _____________________________________________________
4. _____________________________________________________
5. _____________________________________________________
d. Set B
i. ___________How many TOTAL chromosomes?
ii. ___________How many chromosomes are present in each cell of the human?
iii. ___________How many autosomes are present in this karyotype?
iv. ___________How many sex chromosomes are present in this karyotype?
v. ___________Is this karyotype that of a male or female?
vi. Which type of disorder is depicted in this karyotype? Circle one:
Autosomal
or
Sex-Linked
vii. What is the name of this disorder?
________________________________________________
viii. List five characteristics of this disorder.
1. _____________________________________________________
2. _____________________________________________________
3. _____________________________________________________
4. _____________________________________________________
5. _____________________________________________________
e. Set C
i. ___________How many TOTAL chromosomes?
ii. ___________How many chromosomes are present in each cell of the human?
iii. ___________How many autosomes are present in this karyotype?
iv. ___________How many sex chromosomes are present in this karyotype?
v. ___________Is this karyotype that of a male or female?
vi. Which type of disorder is depicted in this karyotype? Circle one:
Autosomal
or
Sex-Linked
vii. What is the name of this disorder?
________________________________________________
viii. List five characteristics of this disorder.
1. _____________________________________________________
2. _____________________________________________________
3. _____________________________________________________
4. _____________________________________________________
5. _____________________________________________________
f.
Set D
i. ___________How many TOTAL chromosomes?
ii. ___________How many chromosomes are present in each cell of the human?
iii. ___________How many autosomes are present in this karyotype?
iv. ___________How many sex chromosomes are present in this karyotype?
v. ___________Is this karyotype that of a male or female?
vi. Which type of disorder is depicted in this karyotype? Circle one:
Autosomal
or
Sex-Linked
vii. What is the name of this disorder?
________________________________________________
viii. List five characteristics of this disorder.
1. _____________________________________________________
2. _____________________________________________________
3. _____________________________________________________
4. _____________________________________________________
5. _____________________________________________________
g. Set E
i. ___________How many TOTAL chromosomes?
ii. ___________How many chromosomes are present in each cell of the human?
iii. ___________How many autosomes are present in this karyotype?
iv. ___________How many sex chromosomes are present in this karyotype?
v. ___________Is this karyotype that of a male or female?
vi. Which type of disorder is depicted in this karyotype? Circle one:
Autosomal
or
Sex-Linked
vii. What is the name of this disorder?
________________________________________________
viii. List five characteristics of this disorder.
1. _____________________________________________________
2. _____________________________________________________
3. _____________________________________________________
4. _____________________________________________________
5. _____________________________________________________
h. Set F
i. ___________How many TOTAL chromosomes?
ii. ___________How many chromosomes are present in each cell of the human?
iii. ___________How many autosomes are present in this karyotype?
iv. ___________How many sex chromosomes are present in this karyotype?
v. ___________Is this karyotype that of a male or female?
vi. Which type of disorder is depicted in this karyotype? Circle one:
Autosomal
or
Sex-Linked
vii. What is the name of this disorder?
________________________________________________
viii. List five characteristics of this disorder.
1. _____________________________________________________
2. _____________________________________________________
3. _____________________________________________________
4. _____________________________________________________
5. _____________________________________________________
Exploration through Reading:
Body cells are called somatic cells. Somatic cells include the skin, liver, muscle, stomach and other bodily cells. The karyotypes
you have completed are from a somatic human cell. The term diploid chromosome number refers to the number of chromosomes
in a somatic cell. The diploid number varies from species to species, however it does not differ from somatic cell to somatic cell
within the same organism. To find your diploid number, simply count the number of chromosomes in your karyotype.
The diploid chromosome number is also called the 2n number.
5. __________What is the diploid chromosome number for your normal karyotypes?
6. __________What is the 2n chromosome number for your normal karyotypes?
The HAPLOID CHROMOSOME NUMBER refers to the number of chromosomes in an organism’s sex cells. i.e.- Sperm in males,
eggs in females. The haploid number, or 1n number is always -half- that of the diploid number.
7. __________What would the haploid chromosome number for your normal karyotypes be?
8. Describe two types of information that can be gained about a child before it is born through a karyotype.
a.
______________________________________________________________________________
______________________________________________________________________________
b. ______________________________________________________________________________
______________________________________________________________________________
Challenge Questions:
9. Why is a karyotype not an ‘assurance’ that an unborn baby is ‘normal’? Be sure to discuss the differences
between chromosomal and genetic abnormalities.
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
10. The most common of all trisomy disorders are Trisomy’s 13, 18, and 21. Why do you think other trisomy’s
involving the other autosomes are lethal to humans?
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
11. A female can survive with only one “X”, yet a male cannot survive with only the “Y”…Why do you think this is
so?
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
12. Would you suppose it possible that an individual would develop to full term and survive with multiple
trisomy conditions that affect several chromosomes? (In other words, can a person have 2, 3, 4 extra
chromosomes?)
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
13. Why do you think people with Downs Syndrome share similar characteristics with regards to physical and
cognitive traits?
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
1
6
2
7
13
19
3
8
14
20
5
4
9
11
10
15
16
21
17
22
12
18
23
male
21
xxy
13
18
jacobs
Set EE
turners
Set F