DNA Unit Plan
Class and grade level: Biology 2, 11th and 12th
Period: 5
(http://www.msu.edu/~lupalisa/webplans/biologyunits/lessoncalendarlog.htm)
Abstract
A pre-assessment will be given to the students before the unit is delivered. The teacher
will set the stage with a series of questions for students to think about: What is it that tells our
cells to produce saliva? What directs a tiny embryo to develop into a baby? What tells skin
cells to grow after cutting your hand? The teacher will present a series of historical experiments
and the resulting data. Students will be asked to think critically and use the data to make
inferences as to what the hereditary material is and its structure. The teacher will represent
DNA replication and protein synthesis using a constructed model. In groups, students will
analyze original and mutated DNA segments to discover the importance and effects of
mutations on protein synthesis. As a class, the causes and effects of genetic disorders will be
discussed. Students will also extract DNA from an onion, cut it with restriction enzymes, and
analyze it using gel electrophoresis. They will also use their understanding of restriction
enzymes and gel electrophoresis to analyze real world problems, such as paternity and crime
scene investigations.
Knowledge: Big Ideas
Past experiments and observations have led to the development of many modern
scientific theories and a large scientific knowledge base. Previous work done by Griffith, Avery,
Hershey, Chase, Chargaff, Franklin, Watson, and Crick has contributed to the understanding of
the hereditary material, DNA.
DNA allows heritable traits to be passed from parent to offspring in sexual or asexual
reproduction. The parent DNA must first be replicated to create an identical copy of itself, which
can then be passed on to an offspring. DNA, being made of two complementary strands, uses
each strand to serve as a template for a new complementary strand. Thus, every time DNA
replicates, each product contains one old strand of DNA and one new strand of DNA.
DNA resides in the nucleus of every cell and is the hereditary material that dictates all
cellular activity. In order to fit inside of the nucleus, the DNA is highly compressed. It contains
the instructions for assembling proteins. Many proteins are enzymes, which catalyze and
regulate chemical reactions within organisms. A gene contains DNA that controls a particular
trait, such as blood type or eye color. Therefore, the DNA of a particular gene codes for a
specific protein that performs a certain function.
DNA undergoes a series of steps in order to be coded into a specific protein. This is
known as the central dogma, which says that DNA codes for the production of mRNA, which is
processed before leaving the nucleus to be translated into a specific protein by a ribosome.
Any alteration in the DNA sequence may lead to an alteration in the amino acid sequence and
possibly change the protein that is produced. Since different proteins perform different
functions, the trait expressed by an individual will be different.
Knowledge: Experiences, Patterns, and Explanations
Observations or experiences
(examples, phenomena, data)
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Transformation (Griffith
experiment)
No transformation in
deoxyribonuclease
experiment (Avery
experiment)
Radioactive phosphorous
found in cell (Hershey-Chase
experiment)
Radioactive sulfur found
outside cell (Hershey-Chase
experiment)
[A] = [T] and [C] = [G]
(Chargaff’s observations)
X-ray diffraction pattern
(Franklin’s observations)
Hybrid 14N and 15N DNA
(Meselson- Stahl experiment)
“Old” students and “new”
students are a part of each
daughter DNA molecule
(Student model activity)
How do you go from gene to
protein (class activity)
Radioactive phosphorous of
bacteriophage found inside
host cell (Hershey – Chase
experiment)
Host cell lyses and new virus
are released
Alzheimers
Muscular Dystrophy
Cystic Fibrosis
Sickle cell anemia
How do you go from gene to
protein (class activity)
Genetic mutation activity
Patterns (laws,
generalizations, graphs,
tables, categories)
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These observations
collectively provide a clear
picture of the DNA and RNA
structures.
DNA and RNA structures
compatible to the
transformation material.
Explanations (models,
theories)
DNA is the hereditary material
Semi-conservative DNA
replication
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DNA contains an “old” and
“new” strand after
replication.
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DNA tells the cell what
proteins to make
DNA transcription mRNA
translation protein (Central
dogma)
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Genetic disorders
Changes in one or more
bases may change the
protein coded for
Mutations have the potential
to alter the physical
expression of an organism.
Application: Model-based Reasoning
Inquiry: Finding and Explaining Patterns in Experience
Practices: Objectives for Student Learning
Objective
Michigan Objectives
1. Describe how genetic material is passed from parent to young during
sexual and asexual reproduction.
Specific Topic Objectives
1. Explain how DNA replicates.
2. Explain how specific proteins are constructed from DNA.
3. Explain how a mutation in a nucleotide sequence may show up as a
change in the trait of an individual (U, III. 3. H. 3: Explain how new traits may
be established in individuals/populations through changes in genetic material
(DNA)).
4. Describe the historical discoveries and experimental data about DNA that
led to the discoveries of its role and structure (R, II.1. H. 7: Describe the
historical, political, and social factors affecting developments in science).
Type
Using
Telling the
story
Using
Using
Reflecting
Daily Lessons
Before Unit Begins (1/19/05): (Pre-assessment)
Pre-assessment (20-25 minutes)
WEEK 1: Monday (2/7/05) - Friday (2/11/05)
Monday (2/7/05): (DNA note pack, DNA overheads, overhead markers, dye
electrophoresis lab)
Series of questions about real world phenomenon: (10 minutes)
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What is it that tells our cells to produce saliva?

What directs a tiny embryo to develop into a baby?
 What tells your skin cells to grow after you cut your hand?
Introduction into the history of DNA: (45 minutes)
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Griffith, Avery, Hershey & Chase experiments
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Allow students the time to analyze experiment outcomes and draw conclusions as a
class
Homework: Dye electrophoresis background questions – due Wed (2/9/05)
Wednesday (2/9/05): (DNA note pack, DNA overheads, overhead markers, lab equipment
& materials, DNA extraction overhead)
Check off HW
Historical DNA discoveries & DNA structure: (60 minutes)
Extraction explanation of procedure, preparation, & distribution of materials (10 minutes)
DNA extraction (20 minutes)
Homework: Read 10.1 – 10.3 (quiz coming up after break)
Friday (2/11/05): (Dye electrophoresis lab, lab overheads, overhead markers, lab
equipment)
Dye electrophoresis purpose, procedure, & distribution of materials (30 minutes)
Student groups
Dye electrophoresis lab (60 minutes)
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Run lab
 Analyze gels & answer questions – TURN IN TODAY
Homework: Read 10.4 – 10.6
Monday (2/14/05 - Friday (2/18/05): NO SCHOOL- Winter break
WEEK 2: Monday (2/21/05) - Friday (2/25/05)
Monday (2/21/05): (Computer with internet, projector & hookups, Journey Into DNA
handout)
Interactive DNA website (55 minutes)
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Representative drawing, title, & notes
 Recap
Homework: Study for quiz on Wed (2/23/05) on DNA history, DNA structure, & dye
electrophoresis
Wednesday (2/23/05): (DNA quiz, DNA model, tape, DNA note pack, DNA overheads,
overhead markers)
Quiz (15 minutes)
Class discussion about cell division (5 minutes)
DNA replication (70 minutes)
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Model (visual)
 Notes (auditory)
Homework: Read 10.7 – 10.14
Friday (2/25/05): (DNA model, tape, DNA note pack, DNA overheads, overhead markers)
Review DNA replication (5 minutes)
 Model
Protein synthesis – Transcription, splicing, translation (70 minutes)
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Model (visual)
 Notes (auditory)
DNA personal ads in groups of 2 or 3 (15 minutes)
Homework: How do you go from gene to protein? HW - due Mon (2/28/05)
WEEK 3: Monday (2/28/05) - Friday (3/4/05)
Monday (2/28/05): (DNA gel electrophoresis lab, lab overheads, overhead markers)
Collect HW
Restriction enzymes & restriction sites (20 minutes)
DNA electrophoresis significance, background, lab set up, & example gel (25 minutes)
Homework: DNA gel electrophoresis practice questions - due Wed (3/1/05)
Wednesday (3/2/05): (DNA gel electrophoresis lab, lab overheads, overhead markers, lab
equipment & materials, review for exam)
Check off HW
Pass out exam review
DNA gel electrophoresis procedure & distribution of materials (10 minutes)
DNA gel electrophoresis lab (30 minutes)
How do you go from gene to protein? HW review (20 minutes)
Protein synthesis review – the bigger picture (30 minutes)
*** stain gels after 1-1 ½ hours and de-stain gel for 24 hours***
Friday (3/4/05): (DNA gel electrophoresis lab, lab overheads, overhead markers, stained
gels from Wed (3/2/05))
Purpose and procedure to analyze DNA gel (30 minutes)
Gel analysis & questions (60 minutes)
Homework: Finish gel analysis questions due – Mon (3/7/05) & read 10.15 – 10.16
WEEK 4: Monday (3/7/05) - Friday (3/11/05)
Monday (3/7/05): (DNA note pack, DNA overheads, overhead markers)
Collect HW
Mutation group activity (20 minutes)
Mutation & genetic disorder discussion (25 minutes)
Homework: Study for exam on Fri (3/11/05)
Wednesday (3/9/05): (Board markers, overheads, DNA model, computer, jeopardy
program)
Review – Q/A
Snowballs review activity (if time remains)
Homework: Study for exam on Fri (3/11/05)
Friday (3/11/05): (DNA exam)