Cootie Genetics

http://www.cbguidesblog.com

http://en.m.wikipedia.org/wiki

What happened to the traits from the Cootie

from the East?

• 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

CootiesTo 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 computer2.) Both mom and day reach into cup #2 and bring out the ear type factor (white or black cube), record this information3.) Both mom and day reach into cup #3 and bring out the eye type factor (purple or yellow cube), record this information4.) Both mom and day reach into cup #4 and bring out the mouth type factor (light green or orange cube), record this information5.) 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 from the East Cootie from the West

Red R Blue r

Wide Ear W Bow w

Plain eye P Lashes p

Lips L Tongue l

Boots B Feet b

Cootie Traits

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

R

r

Cootie from the East

Cootiefrom the west

R

RR

R R

r r

rrr

Punnett Square for the

Heterozygous Cooties—second

generation mating

R

r

First Generation OffspringFi

rst

Gen

era

tion O

ffsp

ring

R RR r

r

r

R

r R r