Download DRAGON GENETICS LAB

DRAGON GENETICS LAB
Principles of Mendelian Genetics
BACKGROUND
Students will work in pairs in the lab to produce a dragon from the random
mixing of genetic traits. Each student will be a surrogate dragon parent. They will pick up
a complete set of dragon chromosomes. Each set must be of the opposite sex, therefore
one parent must pick up the double X chromosomes while the other must pick up the X/Y
chromosomes. The homologous chromosomes will be separated according to Mendel’s
law of Independent Assortment. The genetic codes of that are passed on to the baby will
be recorded on the following pages. The surrogate parents must then decode the genes
inherited by their bundle of joy to determine the phenotype traits of their baby.
PROCEDURES
1. Choose a partner carefully. You and your ‘spouse’ will share the grade for this lab.
This is a no divorce classroom.
2. Each partner must pick up five popsicle sticks --- one of each color of autosome, and
one sex chromosome stick. Each side of the stick represents one allele in the gene
pair of that parent. Together, the two sides are the homologous chromosomes.
3. For each color autosome, and then for the sex chromosome, each parent will randomly
drop his/her stick on the table. The side of the stick that is up represents the
chromosome that is passed onto the baby.
4. The alleles from each pair of homologous chromosomes will be recorded on the charts
on the following pages.
5. The decoding chart on page 2 indicates the phenotypic effect of each gene. The trait
produced by each pair of alleles should be recorded in the data chart next to the
appropriate allele pair. Remember, that a CAPITAL letter is dominant over a
small letter [recessive] unless the decoding chart indicates those traits are co
dominant, sex-influenced, sex-limited, or multi-allelic genes.
6. Answer the questions after the data charts.
DRAGON GENOME
DECODING OF THE GENES
Chromosome
Green Autosome
Dominant genes
Recessive genes
A. no chin spike
B. nose spike
C. no visible ear holes
D. [See Below]
a. chin spike
b. no nose spike
c. visible ear holes
E. long neck
F. no back hump
G. no back spikes
H. long tail
I. flat feet
J. four toes
K. spots on neck
L. [See Below]
M. no fangs
N. spots on back
O. no spots on thighs
P. long arms
Q. small comb on head [see below]
R. [See Below]
S. [See Below]
T. regular thighs
U. red eyes
V. Normal
W. no tail spike
X. no chest plate
Z. non-fire breather
Y. male sex
e. short neck
f. back hump
g. back spikes
h. short tail
i. arched feet
j. three toes
k. no spots on neck
Red Autosome
Orange Autosome
Yellow Autosome
Sex Chromosomes
X Chromosome
Y chromosome
Co dominant Traits
D. eyes pointed at each end
R. Red spots
d. round eyes
r. yellow spots
m. fangs
n. no spots on back
o. spots on thighs
p. short arms
q. large comb on head
t. pointed thighs
u. yellow eyes
v. albino
w. tail spike
x. chest plate
z. fire breather
Dd. Eyes round at front only
Rr. Orange spots
Sex-Influenced Traits
L. wings
l. no wings [dominant in presence of male sex chromosome]
S. no elbow spike
s. elbow spike [dominant in presence of male sex chromosome]
Sex-Limited Traits
Q or q [only males have the comb on the head] [not expressed in females]
NAMES______________________
_______________________
Green Autosome
Genotypes
MOM
DAD
Red Autosome
Genotypes
MOM
DAD
Orange Autosome
Genotypes
MOM
DAD
Yellow Autosome
Genotypes
MOM
DAD
Alleles In
EGG
SPERM
TRAIT- phenotype of the
baby
Alleles In
EGG
SPERM
TRAIT- phenotype of the
baby
Alleles In
EGG
SPERM
TRAIT- phenotype of the
baby
Alleles In
EGG
SPERM
TRAIT- phenotype of the
baby
Sex Chromosomes
Genotypes
MOM
DAD
Alleles In
EGG
SPERM
TRAIT- phenotype of the
baby
Questions:
1. How does dropping the stick on the table and transcribing the letters on the sides
facing up follow Mendel’s Law of Segregation? First define the law.
2. Explain how dropping the green, orange, red, and yellow sticks illustrate Mendel’s
Law of Independent assortment. First state the law.
3. The gene for fangs is recessive, yet most of the dragons have fangs. How can this
happen? [Hint: the gene that causes dwarfism in humans is dominant]
4. What other gene follows the same trend as in question 3? You may have to talk with
other pairs to find out this answer.
5. What is the sex of your baby?
6a. What traits are more likely to be found in males? You may have to talk with other
pairs to find out this answer.
6b. How might these traits be advantages to that sex? [Be creative, but stay clean with it]
7a. What traits are more likely to be found in females? You may have to talk with other
pairs to find out this answer.
7b. How might these traits be advantages to that sex? [Be creative, but stay clean with it]