Cootie Genetics
http://www.cbguidesblog.com
http://en.m.wikipedia.org/wiki
What happened to the traits
from the Cootie from the East?
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Hypothesize what happened to the traits
Design an experiment to test that hypothesis
Predict your results based on your hypothesis
Conduct your experiment
Mating the second generation Cooties
To make a cootie baby:
1.) Both mom and day reach into cup #1 and bring out a body color factor
(red or blue cube), the information will be recorded on the computer
2.) Both mom and day reach into cup #2 and bring out the ear type factor
(white or black cube), record this information
3.) Both mom and day reach into cup #3 and bring out the eye type factor
(purple or yellow cube), record this information
4.) Both mom and day reach into cup #4 and bring out the mouth type factor
(light green or orange cube), record this information
5.) Both mom and day reach into cup #5 and bring out the foot type factor
(brown or green cube), record this information
What does your baby look like? Was your hypothesis supported or refuted?
Do you need to make more babies to figure out what is going on?
Remember, keep it random, nature cannot pick out specific trait factors.
Make 40 babies total.
Why are their two color
cubes in your cups?
Cootie Traits
Cootie from the East
Cootie from the West
Red
R
Blue
Wide Ear
W
Bow
Plain eye
P
Lashes
p
Lips
L
Tongue
l
Boots
B
Feet
b
r
w
Cootie Data
Total # of
Total # of
Total # of
Total # of
Total # of
Total # of
RR
Rr
rR
rr
Red
blue
9
12
9
10
30
10
WW
Ww
wW
ww
Wide-ear
bow
10
15
6
9
31
9
PP
Pp
pP
pp
Plain-eye
lashes
10
9
10
11
29
11
LL
Ll
lL
ll
Lips
tongue
11
11
9
9
31
9
BB
Bb
bB
bb
Boots
feet
9
13
9
9
31
9
What does it all mean
• Trend—30:10 ratio of traits from the east
versus traits from the west—or 3:1 ratio of
dominant to recessive phenotypes
• Trend—10:10:10:10 ratio of trait factors RR, Rr,
rR, rr—or 1:1:1:1 ratio.
• Rr and rR are the same thing– 1:2:1 ratio of
Homozygous dominant (RR) to Heterozygous
(rR & rR) to Homozygous recessive (rr)
genotypes
Punnett Square for the Homozygous
Cooties—first generation mating
Cootie from the East
R
Cootie
from
the
west
R
r
R
r
R
r
r
R
r
R
r
Punnett Square for the Heterozygous
Cooties—second generation mating
First Generation Offspring
r
First Generation Offspring
R
R
R
R
R
r
r
r
R
r
r