Lesson Plan 1 - DNA Unit
Decoding DNA
Biology
Grades 10-12
Time Required: 1½ 50 minute class periods
Overview:
The purpose of this lesson is to introduce the concept that DNA is a code of four nucleic
acids that translate to amino acid chains or polypeptides that are proteins that serve
some function for the organism. Students will also be introduced to the idea that a
change in the code by mutation or other mechanism may or may not change the
resulting protein and may or may not affect the health of the organism.
Instructional Objectives:
• Students will translate a sequence to an amino acid sequence using the universal
codon chart.
• Students will compare resulting peptide chains and be able to identify mutations and
possible biological results of the mutations.
• Students will identify life characteristics resulting from genes.
• Students will understand the model
Curriculum Frameworks: From Oshkosh Area School District Standards and
Benchmarks - Science Biology 1
This lesson provides evidence and discussion that pertain to the following standards:
F1.12.3 Explain current scientific ideas and information about the molecular and genetic basis of
heredity
F1.12.5 Understand the theory of evolution, natural selection, and biological classification
F1.12.6 Using concepts of evolution and heredity, account for changes in species and the
diversity of species, include the influence of these changes on science (e.g., breeding of plants or
animals)
F1.12.8 Using the science themes, infer changes in ecosystems prompted by the introduction of
new species, environmental conditions, chemicals, and air, water, or earth pollution
Materials:
• One sheet lined paper and pencil
• Picture of chromatogram and amino acid sequence
• Movie clip: NOVA http://www.pbs.org/wgbh/nova/genome/program_t.html “Instructions
for a Human Being.”
• Handout of nucleic acid codes for amino acid sequences and codon chart
• movie clip http://www.teachersdomain.org/collection/k12/sci.life.gen.mechdna/ (Click
on the “Common Genetic Code”)
Procedure:
1. Welcome class to a new unit on the code of life, DNA, genes, proteins. Give
students 15 minutes to do formative assessment #15 - “First Word-Last
Word” (Keeley 2008) using the words: GENE, DNA, PROTEIN.
1.1. Have students each pick one line from their First Word to say out loud and
spur some discussion.
1.2. Make class list of questions generated
1.3. Define Gene during discussion of formative assessment. Collect
assessments.
2. Hand out advance graphic organizer for whole DNA unit and explain to students how
they should use it.
3. Show 10 minute movie with interjected lecture: NOVA http://www.pbs.org/wgbh/
nova/genome/program_t.html “Instructions for a Human Being.” Purpose is to
introduce and show how DNA is relevant to our lives today.
4. Put this picture on screen
Copied from site:
http://bioinformatics.utmem.edu/classes/module9/sequencher2.html
Ask students to pair up for the game...”Guess this thing” and take 2 minutes and write in
their lab books as much as they can think of about what they think it is, does, is used
for, represents.... Then show the next thing to guess...
10
20
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40
50
MEDVQNSPAQ VAMPIDRVGV KNLQLPLVVS DRAQGRQHTV ATVDIGVDLP
60
70
80
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100
AHFKGTHMSR FVEALENWTE ELDYASMKRL LEDVKTRLEA RKAYVLFRFP
5.
6. Have one student from each group say what they thought...teacher writes main
points on board. Teacher does not tell students yet what they are.
7. Next hand out a nucleic acid sequence and a codon usage chart with simple
instructions for activity. This is all they get and they must figure out from the clues
on the worksheet how to decode the nucleic acid into Amino Acids represented by
their letters that will spell something. They must find the start and stop codons
themselves by taking time to really look at the chart. The class can help each other
as they figure out the process. Different groups will have slightly different nucleic
acid sequences for later discussion on effect of mutations on AA sequence and
resulting protein function.
8. Go back to the DNA and A.A. sequences and see what students think they are now.
9. Students record results on board and we analyze results by comparing and
resulting AA sequences on computer and by hand. This leads to lecture on
mutations...discuss/lecture on what we see.
9.1. Groups will have different sequences because of small changes or deletions in
the initial nucleic acid sequence. Points=mutations, what can cause changes
in genes, basic genetic diversity, resulting protein functions.
10. Show and browse this website: NCBI website of the genetic related diseases that
have been located through the human genome project. http://www.ncbi.nlm.nih.gov/
books/bv.fcgi?call=bv.View..ShowSection&rid=gnd.preface.91
11. Show movie and lecture on genes as instructions for characteristics and similarities
of genetic code between species http://www.teachersdomain.org/collection/k12/
sci.life.gen.mechdna/ (Click on the “Common Genetic Code”)
12. Homework: describe in one paragraph something in your life that is affected by your
genes (not your jeans!) and explain how.
13. Discuss (very brief) and collect homework. Teacher will read and may make written
comments before handing back.
Assessment:
1. Students will write a paragraph about a genetic trait of theirs or other life that affects
them and how a mutation that changes that trait might affect their lives. This
assignment will allow students to apply their understanding of how genetic code
affects life characteristics.
2. The learning from this lesson will also be assessed in the formative assessment #13:
“Fact First Questioning” (Keeley, 2008) performed 2-3 days later.
2.1. In this activity, I will be assessing the students’ ability to understand beyond
the simple facts about specific concepts, but also introducing novel ideas to
spur questioning and thinking. A list of facts I want to assess is generated.
Then, in a question and answer session with students, the students are
presented with the fact, then asked a why question about the fact with
adequate wait time for them to think. Students must dig deeper than rote
memory to answer these questions. Students may think deeply about these
things for the first time during this exercise, they will become more aware of
their own and their peers’ ideas, and the teacher will gain information of the
depth of understanding surrounding key concepts so far. This information will
be used to adjust future teaching. Some new concepts may also be
introduced as a way to pre-assess later lesson material and activate student
questioning and interest to learn more.
Sources:
• Online Biology Textbook written by J. Kimball: http://users.rcn.com/
jkimball.ma.ultranet/BiologyPages/
• http://www.web-books.com/MoBio/Free/Chap7.htm
•
• NOVA http://www.pbs.org/wgbh/nova/genome/program_t.html “Instructions for a
Human Being.”
•
Copied from site:
http://bioinformatics.utmem.edu/classes/module9/sequencher2.html
20
30
40
50
• 10
MEDVQNSPAQ VAMPIDRVGV KNLQLPLVVS DRAQGRQHTV ATVDIGVDLP
60 70
80
90
100
AHFKGTHMSR FVEALENWTE ELDYASMKRL LEDVKTRLEA RKAYVLFRFP
• NCBI website of the genetic related diseases that have been located through the
human genome project. http://www.ncbi.nlm.nih.gov/books/bv.fcgi?
call=bv.View..ShowSection&rid=gnd.preface.91
• Handout - nucleic acid code and codon usage table
•
• http://www.teachersdomain.org/collection/k12/sci.life.gen.mechdna/ (Click on the
“Common Genetic Code”)
Attachments:
Please see Attachments LINK on WIKI Page