PUTTING DNA to WORK: High School Virtual Field Trip

PUTTING DNA to WORK:
High School Virtual Field Trip
Overview
In this activity teams of students will gather detailed information from the online exhibit
Putting DNA to Work. Students will explore the question:
How can the knowledge of DNA sequencing be applied in the future?
Directions
1. Instruct students to explore the Introduction and DNA Sequence sections of the exhibit.
They may work individually or in groups and may visit the sections in any order.
2. Students should then be assigned to one of three “expert groups” and explore the rest of the
exhibit using their assigned focus.
•
•
•
Forensics: How are sequences used to detect inherited diseases and identify suspects?
Plant Domestication: How is information about plant DNA used to change and improve
agricultural crops?
Public Health: What types of new technology are being used to identify unknown
disease causing agents?
3. Once students have explored the entire exhibit they should remain in their expert groups to
answer the questions.
4. Lead a whole class discussion, allowing each group to report out the information they have
gathered and to discuss answers.
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Introduction
1. Find the percentage of genes that each of the 5 organisms shares with humans.
Organism
Mouse
Fruit Fly
Chimpanzee
Yeast
Plant
Percentage
2. If people share 100% of the same genes, why are we all not identical to each other?
3. Circle the larger item in each pair:
Cells
Tissues
Genes
Chromosomes
4. What is meant by the term “genome”?
5. About how many genes are found in the human genome?
6. You inherit one copy of your genome from each parent.
a. How many copies of every gene sequence do you inherit from your parents?
b. How many chromosomes do you inherit from each parent?
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DNA Sequence
1. Describe the shape of a DNA molecule:
2. What are the building blocks of DNA called?
3. How many kinds of building blocks are there?
4. How can one of the strands of a DNA molecule be used like a photographic negative?
5. When the building blocks pair up, which ones pair together?
6. Probe the DNA sequence using 3 and 6 letter probes and record the number of matches.
Probe
(3 or 6
letters)
CAT
No. Matches
Found on
Screen
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No. Matches Found in the 3
Billion Letter Human Genome
No. Matches Expected in 3
Billion Random Letters
52,612,857
44,767,202
7. How does the length of the DNA probe affect the number of matches the probe will find in
the human genome?
8. If every cell in the body contains all of the same DNA sequence, then why are some cells so
different from others?
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Forensics Expert Group
Your team of experts will gather in-depth information on how sequences are used to detect
inherited genetic diseases and to identify a suspect. The information you gather on these topics
will be vital for the group discussion, which will focus on the question:
How can the knowledge of DNA sequencing be applied in the future?
Explore the Inherited Diseases and DNA & Criminal Justice sections and use the following
guiding questions:
1. What is a mutation?
2. For each mutation identify the changes in the message:
TMET OD REAM
Single letter change
EMIT TO DREAM
Insertion
TIIM ET ODREAM
Deletion
TAME TO DREAM
Reverse
3. Why do you need to look at two copies of a gene to tell if a person has inherited a disease?
4. What is meant by the term “carrier”?
5. How many letters are involved in the genetic defect that causes sickle cell anemia?
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6. Hemochromatosis is an inherited genetic disease.
a. What happens to a person with hemochromatosis?
b. What procedure do doctors use to treat hemochromatosis?
7. How could the falsely imprisoned benefit from DNA sequencing technology that might not
have been available at the time of their original trial?
8. How many sites in the DNA sequence are used by the FBI’s Combined DNA Index System
(CODIS)?
9. What are the chances of a suspect perfectly matching a sample at all CODIS sites?
10. Use the interactive to compare DNA samples from 3 suspects to a DNA sample left behind at
the scene of a crime.
a. Which suspect matches the sample?
b. Which suspect is probably a sibling?
c. Which suspect is most likely unrelated to the other two?
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Plant Domestication Expert Group
Your team of experts will gather in-depth information on the use of DNA sequencing information
from plants to change and improve agricultural crops. The information you gather on this topic
will be vital for the group discussion, which will focus on the question:
How can the knowledge of DNA sequencing be applied in the future?
Explore the Improving Crops section and use the following guiding questions:
1. Agricultural crop plants look very different from the original wild plant ancestors of years ago.
What techniques did our human ancestors use to help create these changes?
2. List three differences between the following characteristics of ancient teosinte and modern
corn (maize).
a. Ears:
b. Kernels:
c. Number of branches:
3. How is a genetically modified organism (GMO) created?
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Using the Maize Mutants interactive, your group should complete the following chart by finding
2 genes that control each of the following characteristics of the corn plant:
4. Kernel color:
Chromosome #
Name of gene
What does this gene do to the plant?
5. Leaf texture or color:
Chromosome #
Name of gene
What does this gene do to the plant?
6. Silk/Tassels:
Chromosome #
Name of gene
What does this gene do to the plant?
7. What does the "transgenic" gene on chromosome 7 increase resistance to in Bt crops?
8. Compare the amount of modern corn produced per acre in 2002 with the amount that would
be produced by teosinte if it was used as a crop plant today.
Corn
Yield (tons per acre)
Teosinte
9. If we were still planting teosinte as a food crop, how much more land (in millions of acres)
would be needed to get the same yield as modern corn (2002 figures)?
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Public Health Expert Group
Your team of experts will gather in-depth information on new technology using DNA sequences
to quickly identify unknown disease causing agents. The information you gather on this topic
will be vital for the group discussion, which will focus on the question:
How can the knowledge of DNA sequencing be applied in the future?
Explore the Infectious Disease section and use the following guiding questions:
1. What does SARS stand for?
2. Using the Identify the Disease activity try to quickly identify what virus the sequence belongs
to. What is the name of the virus that matches the unknown DNA sequence?
Human
virus 3
3. What new DNA technology was used as an identification tool to find the cause of SARS?
4. Answer the following questions about creating a virus chip:
a. When creating a virus chip, how many viral DNA sequences (or dots) are contained on the
grid?
b. How many base pairs, or letters, are contained in each DNA sequence?
c. How many different virus strains are represented on the chip?
d. The virus chip produces different colored dots. What color dots indicate sequences that
match the unknown virus?
e. What determines the brightness of each bar on the bar code?
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6. Which was faster and easier to use in finding a match for the human parainfluenza virus 3,
the method using DNA letter sequences or the method using bar codes?
Why?
7. What virus family is the SARS virus most closely related to?
8. What animals do scientists think are the most likely sources of SARS?
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This activity addresses the following Next Generation Science Standards and Common Core State
Standards for high schools.
Next Generation Science Standards
Standards
• HS-LS1 From Molecules to Organisms:
Structures and Processes: HS-LS1-1
• HS-LS3 Heredity: Inheritance and
Variation of Traits: HS-LS3-1, HS-LS3-2
• HS-LS4 Biological Evolution: Unity and
Diversity: HS-LS4-1
Science and Engineering Practices
• Asking questions (for science) and
defining problems (for engineering)
• Constructing explanations (for science)
and designing solutions (for
engineering)
• Engaging in argument from evidence
• Obtaining, evaluating, and
communicating information
Common Core State Standards
ELA/Literacy
• Literacy in Science and Technical
Subjects (Grades 11 and 12): RST.1112.1, RST.11-12.9
• Writing (History/Social Studies,
Science, and Technical Subjects):
WHST.9-12.1, WHST.9-12.2, WHST.912.9
• Speaking and Listening (Grades 11 and
12): SL.11-12.4
Mathematics
• Standards for Mathematical Practice:
MP.2
Crosscutting Concepts
• Patterns
• Cause and effect: Mechanism and
explanation
• Structure and function
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