c.
Blackline Master
A DNA molecule has a ladder shape. Deoxyribose
molecules bond with phosphate molecules to make up
the sides of the ladder (a). The bases bond to form the
rungs of the ladder (b). Hundreds of thousands of
nucleotides make up DNA. DNA is twisted tightly to
make up a chromosome (c). Segments of DNA make
up genes. A gene provides each cell with instructions
for making a particular protein.
Fit six nucleotides together to form a row with the
following sequence of bases.
guanine
thymine
adenine
cytosine
cytosine
guanine
a.
b.
new
nucleotides
are added
here
This arrangement of nucleotides will be used
to represent the left half of the molecule.
Now, complete the right side. Can you make
up a rule to follow when pairing the bases?
Rule:___________________________________________
_________________________________________________
Your completed model should look like
a ladder.
DNA model closed
DNA model open
ready for replication
* Visit the Human Genome pod of Genetics: Decoding Life
(2 copies per student)
Blackline Master
* Visit the Human Genome pod of Genetics: Decoding Life
Blackline Master
The Museum has put together a survey in which we ask our guests about their
opinions on the use of technologies associated with the Human Genome
Project. The same genetic technologies that allow us to analyze our own DNA—
offering new opportunities for the diagnosis and treatment of diseases—also
raise complex social and ethical questions.
Before your visit to the Museum, read the statements below. We present
these statements to our visitors and ask them to choose the area that is most
important to them. At the Museum, interact with the voting panel and think of
two of your own issues to add to the survey.
Large DNA databases are
important in understanding
the genetic cause of disease.
There would be no guarantee
that an individual’s genetic
information would remain
private.
Having my DNA profile on
record could put me at risk
for discrimination.
Scientists could use this
information to quickly
develop drugs for more
diseases.
The complex issue of gene
patenting should be
carefully studied.
DNA databases could aid in
identifying missing persons
and victims of war or natural
disasters.
Large DNA databases could
have enormous potential for
medical research.
We would not have control
over how our DNA
information is being used.
Genetic Engineering
Genes can be moved around, even between species. That’s because DNA
is the same kind of molecule no matter what organism it comes from.
Scientists can cut and paste pieces of DNA in the same way we cut and
paste words in a word processing document. The process of cutting and
pasting DNA is called recombinant DNA technology or genetic
engineering. Scientists use genetic engineering for agriculture, medicine
and research. One of the benefits of genetic engineering is the
development of plants that are resistant to disease or infestation.
Without this biotechnology, if one plant species gets a disease, others
of its kind get it, too.
Preparing for your visit …
• Complete one or more of the following activities:
q Visit the Museum’s website at
www.msichicago.org/exhibit/genetics/enginee
ring.html and watch the video “Green-Eyed
Frogs.”
q
Discuss the following: In nature, frogs do not
have eyes that glow in the dark. Why do
scientists genetically engineer frogs to make
their eyes glow? How did these frogs get their
glow-in-the-dark eyes?
q
Engage in the hands-on genetic engineering
activity “Yellow Dent Corn.”
• Read the “Genetic Engineering” reading passage (page
27) with your class.
• As a class, brainstorm questions you can investigate
about genetic engineering while at the Museum.
(Suggestions for questions: How is genetic engineering
used? What are the ethical issues of genetic engineering?
How can genetic engineering improve life on Earth?)
• Focus words should be chosen on the day the questions
are formed. As the questions are formed, list words on the
board, and then groups choose words that are related to a
question they want to research.
•
Have each student choose a question to research and
write it at the top of his or her “Museum Trip Organizer.”
•
In groups, begin to fill out the Word Knowledge sheet for
a word related to “genetic engineering.” (Suggestions:
DNA, genes, genetic engineering)
During your visit…
•
Engage in the interactive kiosks in the Genetic
Engineering Pod of the Genetics: Decoding Life exhibit:
“Be a Scientist,” “Doctoring or Designing,” and watch
the engineering genes video.
•
Visit the Corn shed in The Farm exhibit. What did you
find out about hybrids in this exhibit?
•
Using their “Museum Trip Organizer,” have student
collect information that will help answer their questions.
After your visit …
•
Complete the “Word Knowledge” sheet.
•
Create class displays or interactive activity to teach other
classes about genetic engineering.
Blackline Master
Use index cards to demonstrate how corn and genetically engineered corn react
differently to disease. Side one of each index card will represent the
original organism, specifically Yellow Dent corn plants. When disease hits a field
of regular corn, it spreads quickly because all the plants are the same. Side two
will represent genetically engineered corn. With this type of corn,
the field still gets a disease, but its spread is controlled because the corn plants
have been genetically engineered to resist the disease.
Regular Corn:
1. Mark side one of each card with a “C” For Yellow Dent corn.
2. Give each student one card.
3. Instruct each student to have five other students write their names on the
side of the card where the “C” was written and to remain standing when they
are finished.
4. You will represent the disease. Touch one of the students. That student sits
down (they are “dead”) and reads the names on her card. As the names are
read, those students also sit since they have been "touched" by the disease.
5. Have another of the seated “dead” read the names on their card. This process
continues until almost all of the students are sitting.
6. Ask students to explain why the disease spread so fast
(they are genetically similar).
Genetically Engineered Corn:
1. Flip over each card and label one-fourth of the cards with “C” for Yellow
Dent corn and three-fourths with “CGE” for “Corn that has been
Genetically Engineered.”
2. Repeat steps 2-6 above. This time only those students who are connected to
the diseased “C” and are “C” themselves will sit. The “CGE” don't die even if
they are touched by disease.
3. Almost all of the students will remain standing (“alive”).
4.Ask students to explain why the disease didn't spread as fast among the
genetically engineered corn plants as it did among the regular corn. In which
cornfield would you need to use more chemicals to control disease? Why?
5. Ask students to summarize what this simulation symbolized.
* Visit the Genetic Engineering pod of Genetics: Decoding Life
Cloning
Cloning is using DNA of one organism to make another that shares the
same genes. While many different kinds of animals have been clones, the
first advanced mammal to be cloned was Dolly, a sheep, in 1996.
Scientists used three different sheep to create Dolly; the DNA donor, the
egg donor and the surrogate.
Preparing for your visit …
•
Complete one or more of the following activities:
q
Use the blackline master, Cloning, to foster
discussion on cloning.
q
Visit the Museum web site
www.msichicago.org/exhibit/genetics/cloning.htm
l and engage in the activities “Has this animal
been cloned?” and “Cloning a Mouse.” Discuss
why scientists use three different colored mice for
cloning.
•
Read the “Cloning” reading passage (page 27) with your
class.
•
As a class, brainstorm questions you can investigate
about cloning while at the Museum. (Suggestions for
questions: Why should cloning be done? Can cloning be
used for medical purposes? Why do scientists make
clones? How can cloning be used to improve the quality
of life?)
•
Focus words should be chosen on the day the questions
are formed. As the questions are formed, list words on the
board, and then groups choose words that are related to a
question they want to research.
•
Have each student choose a question to research and
write it at the top of his or her “Museum Trip Organizer.”
•
In groups, begin to fill out the Word Knowledge sheet for
a word related to the topic “cloning.” Suggestions: clone,
identical, twin, copy)
•
As a class, brainstorm questions you can investigate
about cloning while at the Museum. Have each student
choose their own question to research and write it at the
top of their “Museum Trip Organizer.”
During your visit…
•
Engage in the interactive kiosks in the Cloning Pod of the
Genetics: Decoding Life exhibit: “Be a Scientist,”
“Cloning People,” “You Decide,” “My Clone/My Twin,”
and watch the “Cloning at Work” video.
•
Using the “Museum Trip Organizer,” students collect
information that will help answer their questions.
After your visit…
•
Complete the Word Knowledge sheet.
•
Create class displays or interactive activities to teach
other classes about cloning.
Blackline Master
Sheep A
Nuclear DNA
taken from
udder cell from
sheep A
Sheep B
DNA
removed
from egg cell
of sheep B
DNA from
sheep A
implanted in
enucleated cell
from sheep B
Embryo placed in
womb of
sheep C
Sheep C
Surrogate Mother
* Visit the Cloning pod of Genetics: Decoding Life
Embryo
grown in
test tube
Dolly born as
sheep A’s
clone
Development
How does a fertilized egg become a fish, a mouse, a chicken or a human
baby? It’s all related to DNA, genes and the environment. Different
animals require different lengths of time for development, but the basic
process inside the embryo is similar for all of them.
Preparing for your visit…
•
Complete one or more of the following activities:
q
Visit the Museum website at
www.msichicago.org/exhibit/genetics/develop.html
and engage in the activity “Elderly Worms.” Discuss
why a scientist would study worms to learn about
aging.
q
Use the blackline master “Development of an Egg” to
foster discussion on the changes taking place as the
egg develops into a chick.
q
Dissect a raw, unfertilized egg.
1. Students in groups carefully break open an egg and
record their observations.
2. Students should hypothesize the functions of the
various structures they see.
3. Give out the reading passage on development and
tell the students to draw a picture of their egg and identify
structures.
4. Have students share their pictures.
5. Finally, put up the blackline overhead and have
students compare their drawings to the overhead.
•
As a class, read the development reading passage,
“Development: Structure of the Egg,” (page 28) and
brainstorm questions you can investigate about
development while at the Museum. (Suggestions for
questions: How does an egg become a chick? Why do
scientist study development in animals? How do you
construct an animal from a single cell?)
•
Focus words should be chosen on the day the questions
are formed. As the questions are formed, list words on the
board, and then groups choose words that are related to a
question they want to research.
•
Have each student choose a question to research and
write it at the top of his or her “Museum Trip Organizer.”
•
In groups, begin to fill out the Word Knowledge sheet for
a word related to the topic “development.” Suggestions:
development, fertile, embryo, germinal disc)
During your visit…
•
Engage in the interactive kiosks in the development pod:
“Nematode Worms,” “Zebrafish,” “Make a Fish” video
and “Chromosome 21.”
•
Explore the Prenatal Development exhibit on the back
wall of the west balcony.
•
Using their “Museum Trip Organizer,” have students
collect information that will help answer their questions.
After your visit…
•
Complete the “Word Knowledge” sheet.
•
Create class displays or interactive activities to teach
other class about development.
Unfertilized Egg
shell
air cell
Blackline Master
vitelline membrane
Germinal Disc:
a disk-like spot on the yolk where fertilization
takes place
yolk
Albumen (or white of the egg):
a nutrient protein
Yolk (or yellow part of the egg):
nourishes a developing embryo
Vitelline membrane;
the outer covering of the yolk
Chalazae:
the twisted bands of dense albumen attached to
the yolk that serve to support the yolk.
germinal disc
membranes
albumen or white
1 day
7 days
14 days
chalaza
21 days
* Visit the Development pod of Genetics: Decoding Life and prenatal development in the Grainger Hall of Basic Science
General Post-Visit Activities
•
Create classroom displays about genetics,
highlighting the five areas focused on in the
Genetics: Decoding Life exhibit.
•
Write a poem or song about genetics. The activity
“Journey into DNA” on the PBS website at
www.pbs.org/wgbh/nova/genome/dna.html uses a
poem to explain DNA.
Blackline Master
We often take the word mutant to mean something strange or deformed. But
really we are all mutants of one another. Mutations—random genetic accidents
are the ultimate source of all genetic variation. Without mutations, there would
be no variety; and without variety there would be no evolution. If it wasn’t for
mutations, the earth would still be populated by a mass of identical molecules
swimming around in the primordial soup.
(excerpted from Get a Grip on Genetics, Time Life Books)
Any type of organism can be identified by examination of DNA sequences unique
to that species. Identifying individuals within a species is less precise at this time,
although when DNA sequencing technologies progress farther, direct comparison
of very large DNA segments, and possibly even whole genomes, will become
feasible and practical and will allow precise individual identification.
To identify individuals, forensic scientists scan about 10 DNA regions that vary
from person to person and use the data to create a DNA profile of that individual
(sometimes called a DNA fingerprint). There is an extremely small chance that
another person has the same DNA profile for a particular set of regions.
Some Examples of DNA Uses for Forensic Identification:
• identify potential suspects whose DNA may match evidence left at crime scenes
• exonerate persons wrongly accused of crimes
• identify crime and catastrophe victims
• establish paternity and other family relationships
• identify endangered and protected species as an aid to wildlife officials
(could be used for prosecuting poachers)
• detect bacteria and other organisms that may pollute air, water, soil and food
• match organ donors with recipients in transplant programs
(excerpted from www.ornl.gov/hgmis, a website sponsored by the U.S. Department of Energy Office of
Science, Office of Biological and Environmental Research, Human Genome Program)
* Visit the Mutations and Human Genome pods of Genetics: Decoding Life
Blackline Master
Imagine that, you are a scientist who specializes in genetic engineering. For
the past few years, farmers have been complaining about potatoes beetles eating their crops. Since potatoes are one of your favorite foods, you take a personal interest in this problem.
The first thing you do is visit potato farms and ask farmers what type of potato seeds they’re planting. Some of the farmers report they are trying a new
hybrid seed that was made by crossing a high-yield plant with a fast-growing
plant. Although this hybrid does increase yield slightly, most of the crop is
still lost to the beetles. The farmers tell you the only way they can increase
their potato yield is to spray pesticides, which consumers don’t like.
After much research, you discover that a certain type of bacteria repels
insects. You cut a DNA strand from this bacterium and insert it into potato
DNA. The new genetically engineered potato plant is bug-resistant. Now,
farmers will be able to harvest more potatoes and feed more people. Time
magazine interviews you for a feature story on genetic engineering. The
reporter asks what your next project will be. What do you say?
The year 1996 saw a scientific breakthrough that few people had expected so
early. It was the cloning of a sheep, an animal much more complex than
simple plants or bacteria.
To create the sheep, a team of scientists from Scotland, led by researcher Ian
Wilmut, took a nucleus from the udder of a female sheep. They joined this to
an unfertilized egg cell from another sheep, having first removed all nuclear
material from the egg. The joined cells grew into an embryo, which was then
put into the womb of a third sheep. From there on, pregnancy and birth were
normal. When born, the lamb (named Dolly) was also perfectly normal,
except that she had no father. She was exactly like the sheep from whose udder
the cell had been taken.
(excerpted from Cloning Frontiers of Genetic Engineering, David Jefferis)
* Visit the Genetic Engineering and Cloning pods of Genetics: Decoding Life
Blackline Master
The egg is a biological structure intended by nature for reproduction. It
protects and provides a complete diet for the developing embryo and serves
as the principal source of food for the first few days of the chick's life. The
egg is also one of the most nutritious and versatile of human foods.
When the egg is freshly laid, the shell is completely filled. The air cell is
formed by contraction of the contents during cooling and by the loss of
moisture. A high-quality egg has only a small air cell.
The yolk is well-centered in the albumen and is surrounded by the vitelline
membrane, which is colorless. The germinal disc, where fertilization takes
place, is attached to the yolk. On opposite sides of the yolk are two twisted,
whitish cord-like objects known as chalazae. Their function is to support
the yolk in the center of the albumen. Chalazae may vary in size and density
but do not affect either cooking performance or nutritional value.
A large portion of the albumen is thick. Surrounding the albumen re two
shell membranes and the shell itself. The shell contains several thousand
pores that permit the egg to "breathe."
(excerpted from www.urbanext.uiuc.edu)
* Visit the Development pod of Genetics: Decoding Life
Genetics: Decoding Life Module was funded by a grant from the Polk Brothers Foundation.
Curriculum writers
Pamela Barry, education coordinator, Museum of Science and Industry
Joy Reeves, teacher, Chicago Public Schools
Sarah Tschaen, education coordinator, Museum of Science and Industry
Melanie Wojulewicz, teacher/administrator (retired), Chicago Public School Science
Design, illustration and production by KerrCom Multimedia