Genetic Traits
We will begin by working this first experiment.
1. Genetic traits are things we can see with our eyes that are the result of having
certain gene(s) - hair color, eye color, and the traits listed below.
2. Each person has thousands upon thousands of genes that contribute to our
appearance as well as who we are. Genes are very small so we can't see them,
only the effect they have on us.
3. We each carry two copies of genes in every cell of our body (except the sperm
and egg cells..): one set comes from each parent. For this reason people often say
how much we look like our parents, siblings, and relatives. We look alike because
we share many common genes.
4. It also may be useful to mention that as individuals we are the sum of our "genes"
and also of our environment (so genes control a lot, but they don't control
everything!).
Who has the following traits? Work in groups of 4 and put your information on a
page, which will then need to be transferred to a group page.
Tongue rolling - stick your tongue out and see if you can roll the edges into a loop. This
trait is *thought to be* dominant, meaning you only need one "working" copy of the gene
to have it - Tt, or TT. I say "thought to be dominant" as there have been studies
suggesting that the trait can be learned. Additionally, identical twins do not always
share the tongue rolling trait - a piece of information which indicates that it may not be
genetically controlled. I present it, however, as it is a simple test, and because most kids
raise no objection to an opportunity to stick out their tongues.
Hitchiker's thumb - Stick your thumb up, as though "thumbing" a ride. You have the
trait if the first part of the thumb bends back more than 45 degrees. This trait is recessive
meaning you need two copies of the gene to have it (hh).
Ear lobe attachment - See whether the ear lobes are attached to the side of the head, or
whether they hang freely. Unattached earlobes are dominant to attached earlobes.
Widow's peak - People whose hair comes to a point over the middle of their forehead
have a widows peak (a dominant trait).
A number of K-12 schools have online projects to collect data concerning genetic traits.
Your students can use the WWW to submit their information to some of these projects.
For homework, please try and check at home if your parents and or siblings have the
same traits. What did you find?
2. So, you know that traits are carried from one generation to the next. How is this
done? To answer this question, as well as the following questions, please go to the
following link:
http://kidshealth.org/teen/your_body/health_basics/genes_genetic_disorders.html#
1. What are genes?
2. How many chromosomes do humans have?
3. Where are genes carried? How do they work? What is meant by genes being
dominant or recessive?
4. What is a gene mutation?
5. What is gene therapy?
Please use the following link to look at a map of the human chromosomes.
http://web.rollins.edu/~jsiry/HUMAN-1.gif
3. What can gene mutations cause? There are many genetic disorders and your job will
be to pick one and make a quick presentation to the rest of the class. Your presentation
should be done with the use of multimedia and will be the notes for everyone to use.
When describing the mutation you should focus on: how is it caused, symptoms, effects,
how common, treatment, and interesting facts. So, when you are done you should have a
small write up about the disorder outlining each of the above points, as well as a
multimedia presentation that can be shown to the rest of the class.
DCS
Genetic Disorder
Name: ________________________
Teacher: Mr. Schlosser
Date of Presentation: ____________
Title of Work: ___________________
Criteria
1
2
Points
3
4
Student presents
Audience has
Audience cannot
Student presents information in
difficulty
understand
information in
logical,
following
logical sequence
interesting
Organization presentation because
presentation
there is no sequence
which audience sequence which
because student
of information.
can follow.
audience can
jumps around.
follow.
Student is
Student
Student does not have uncomfortable
demonstrates full
grasp of information; with information Student is at ease knowledge (more
Content
student cannot
and is able to
with content, but
than
Knowledge
answer questions
answer only
fails to elaborate. required)with
about subject.
rudimentary
explanations and
questions.
elaboration.
Student used
Student occasional
Visuals related to
visuals to
Student used no
used visuals that
text and
reinforce screen
Visuals
visuals.
rarely support text
presentation.
text and
and presentation.
presentation.
Presentation has
Presentation had
Student's presentation
no more than two Presentation has
three misspellings
had four or more
misspellings
no misspellings
and/or
Mechanics
spelling errors and/or
and/or
or grammatical
grammatical
grammatical errors.
grammatical
errors.
errors.
errors.
Student mumbles,
Student
incorrectly
incorrectly
Student used a
Student's voice is
pronounces terms, pronounces terms.
clear voice and
clear. Student
and speaks too
Audience
correct, precise
Delivery
pronounces most
quietly for students in members have
pronunciation of
words correctly.
the back of class to difficulty hearing
terms.
hear.
presentation.
Total---->
Teacher Comments:
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