Download Genes are pieces of information in the form of DNA that tell the cells

Genes are pieces of information in the form of DNA that tell the cells of an organism what to do in order to
function. For example, your muscle cells need to make muscle proteins so that you can move; the
information to make the muscle protein is stored in your genes. Parts of you are easy to see such as your hair
and eyes. But some parts are not so easy to see, such as the enzymes that digest your food. All of these
components, that make up you, are determined by your genes. In the Cootie game we called the components
that made up the cootie traits or characteristics.
You have two copies of all of your genes, one that you received from your mom and one that you received
from your dad. For most of your traits the gene you got from your mom is the same as the gene from your
dad. However there is variation of some genes. An example of this is eye color. The variation can be due to
two or more versions of a gene for a trait. Two versions of a gene are called alleles. For example:
blue/brown eye color exists because of two alleles of a gene. If you have two blue alleles of the eye color
gene (remember you got one allele from mom and the other from dad) then you have blue eyes. If you have
two brown alleles then you have brown eyes. But what happens if you got a blue and a brown? Perhaps the
color blends and you get kind of a grayish, purplish eye color? It turns out, though, that generally traits do
not blend and what you get if you have one blue and one brown allele is brown eye color. So what happened
to the blue? The blue is still there but not seen. For most genes one of the alleles overrides information of
the other allele. The allele that you see (brown in this case) is called dominant, whereas the allele that you
do not see (blue) is called recessive. Which alleles were dominant for the five different cootie traits you
observed
If an individual has the same allele for a specific gene version they would be homozygous for that gene; two
different alleles would be heterozygous. Because blue eye color is recessive, in order to have blue eyes you
would have to be homozygous for this gene, both of your eye color genes would have to be blue. However
if you were heterozygous (Brown/blue) or homozygous (Brown/Brown) then you would have brown eyes.
The 5 visible Cooties traits are:
Body/Head color
Auditory Appendages (Ears)
Ocular Appendages (Eyes)
Vocal Appendages (Mouth)
Motility Appendages (Legs)
In the population of Cooties that you reproduced, each of the above traits had two (2) possible versions
(alleles) that can result in differences in the visible trait.
Body color-Red or blue (Red is dominant to blue)
Auditory Appendages-Wide-ear or bow (Wide-ear is dominant to bow)
Ocular Appendages-Purple or lashes (Purple is dominant to lashes)
Vocal Appendages-Lips or tongue (Lips are dominant to tongue)
Motility Appendages-boots or bare-feet (boots are dominant to bare-feet)
During the mating of the cooties you were able to make cooties with different combinations of alleles than
what you started with in Mom and Dad or even Grandma and Grandpa. Remember Mom and Dad were both
Heterozygous for all five traits. Their genotype would be RrWwPpLlGg (mom) and RrWbPlLtGb (dad),
while their phenotype is Red body, wide ear, purple eye, lips and boots. Genotype refers to the allele
combination, whereas phenotype is the trait that we can see. Also remember Grandma’s genotype was
RRWWPPLLGG and Grandpas rrwwppllgg. Can you see why the babies from the mating between the
cootie from the east (Grandma) and the cootie from the west (Grandpa) resulted in only heterozygous babies
that all looked like Grandma?