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Wood to Wheels- Inquiry Lesson Plan
Lesson Introduction

Title: Bioenergy in the Classroom

Subject/ target grade: 9-11

Duration: approximately 6 days (55 minute class periods)
o Greener Diet Article: ½ day – follow with powerpoint (55 minute class period)
o Growing Fuel Powerpoint:: 2-3 days (55 minute class period)
o Wheat Germ DNA Extraction Lab: 1 day (55-70 minute class period)
o DNA Decoder activity: 1 day (55-70 minute class period)

Setting: classroom

Learning Objectives: Students will be able to….
o Describe how food and food production affect global warming
o Identify the 4 nitrogenous bases associated with DNA
o “Decode” a hypothetical strand of DNA
o Describe the structure and components of cell walls
o Improve a hypothetical “cell wall” by creating genetic modifications through peer
collaboration
o Articulate 2 challenges facing scientists who are working on biofuels and 2 possible solutions

Michigan Content Expectations:
Inquiry, Reflection and Social Implications
 B1.1C: Generate questions from investigations
 B1.1E: Give evidence to support conclusions
 B1.2B: Apply science to social issues
 B1.2E: Be aware of careers in science
 B1.2i: Explain progressions of ideas
 B1.2k: Analyze how science and society interact
Chemistry and Biochemistry
 B2.2f: Explain the role of enzymes and other proteins in biochemical functions
 B2.5A: Recognize and explain that macromolecules such as lipids contain high energy
bonds
Cell Structure and Function
 B2.5i: Relate cell parts/organelles to their function
Homeostasis and Health
 B2.3A: Describe how cells function in a narrow range pf physical conditions, such as
temperature and pH to perform life functions
Human impact of ecosystems
 B3.4C: Examine the negative impacts of human activities
 B3.4d: Describe the greenhouse effect and list possible causes
 B3.4e: List the possible causes and consequences of global warming
DNA/RNA and Protein Synthesis
 B4.1B: Explain that information is passed by genes that code for DNA, these genes
produce proteins
 B4.2B: Recognize that every species has its own characteristic DNA sequence
 B4.2C: describe the structure and function of DNA
 B4.2D: Predict the consequences that changes in DNA composition of a particular
gene may have on an organism

B4.2f: Demonstrate how genetic information in DNA molecules provide instructions
for assembling proteins
 B4.2g: Describe the process of replication, transcription and translation and how they
relate to each other in molecular biology
 B4.4c: Explain how mutations in the DNA sequence of a gene may be silent or result
in phenotypic change in an organisms and in its offspring
Mendelian and Molecular Genetics:
 B4.2h: Recognize the genetic engineering techniques provide great potential and
responsibilities
 B4.4a: Describe how inserting, deleting or substituting DNA segments can alter a gen

Lesson Overview: Students will investigate how the food they eat and its production effect the
global climate. They will be introduced to the importance of bioenergy, our energy issues, the impact
of those issues, and possible solutions. Students will investigate how changes in DNA can aid in
producing plants that have higher levels of cellulose, which is important in producing ethanol.
Lesson Core

The Guiding Question:

Materials and Equipment Needed:
1. Day 1: Greener Diet Article
 “Greener Diet” article http:www.sciencenewsforkids.org/articles/20090225?Note2.asp
2. Day 2-3: Bioenergy in the classroom
 Powerpoint- to be revised and attached at a later date
3. Day 4: Wheat Germ DNA Extraction Lab
 wheat germ- I level teaspoon
 liquid detergen- 1 ml
 Ethyl Alcohol (95%)- 15 ml (COLD) on Ice
 50o – 60o Celsius tap water – 20 ml
 Hot plate with Beaker of Tap Water
 Thermometer
 2 - 50 ml beakers
 1 - Graduated cylinder (large)
 Glass stirring rod for stirring mixture
 Paper towel or Eye dropper – may be needed to remove
foam
 Paper clip hook or wooden stick or spaghetti for collecting
DNA
4. Day 2-3: Cell Wall Recipe
 Strips of construction paper (3 different colors)
 DNA strips (included in handouts)
 Scissors
 Glue
 DNA decoder (included in handouts)
 Poster board or large paper

Safety precautions:
Ethyl and isopropyl alcohol, 95%, are flammable and dangerous fire risks; keep from flame and
sources of ignition. Both alcohols are also toxic by ingestion. Chemical splash goggles are
advised whenever heat and glassware are used.

Advanced Preparation
Obtain wheat germ from health food store or many supermarkets

Background Information for Teachers:
Lesson adapted from: US Department of Energy. “Cell Wall Recipe: A lesson in Biofuels”. Author:
Daniel Steever. Owner: National Renewable Energy Laboratory
In these activities, students will investigate how changes in the DNA sequence
that codes for cell wall formation can have a favorable outcome in producing plants
that have higher levels of cellulose than the parent plant. It is the yield of cellulose
that is most important in the production of ethanol, and the greater the amount of
cellulose there is within in the cell wall, the greater the amount of ethanol that can be
produced. To engage students, the first part of this lesson has students participating in
a discovery activity where they will extract DNA from wheat germ.
Following this, students will be given 3 strips of paper at random with different
symbols on them; these strips are the DNA strands. While each strip has four symbols,
only three symbols represent a gene (a codon, to be specific) and students will read the
strips from left to right. By having four symbols per strip, students will have a variety
of possible combinations as they lay out their strips to be decoded. Students will look at
the key provided and build their cell walls based on the genetic code they were
given. Students can make adjustments in their code if they have a fatal mutation or they
did not get a gene for cellulose, lignin, or hemicellulose. Once students have built
their cell walls they will evaluate the codes that would be most favorable in
producing cell walls with a high percentage of cellulose and low percentages of lignin
and hemicellulose. This module can be used as part of a whole unit or as an activity
in understanding cell wall structure and function, DNA and genetics, evolution,
technology, or science and society.

Engage:
Students will begin by reading the article “Greener Diet”, by Stephen Ornes from Science News
forKids Feb 25, 2009. The article reports on new studies by scientists attending the American
Association for the Advancement of Science in Chicago, Illinois, which show how food and its
production can affect the planet and its warming climate. Researchers have warned that too much
eating of meat can help make the planet warmer and put off too much carbon dioxide which is
considered as a greenhouse gas. It affirms that eating vegetables like potatoes can help in easing the
release of carbon dioxide to the atmosphere.
Students will use a Writing in Science strategy to write a scientific explanation that identifies the
claim made by the author. Students will indicate whether the claim is valid or not and support their
reasoning with at least 3 pieces of supporting evidence. Should people eat less meat to help the
environment? Class discussion will follow- key points will be recorded on large post it chart paperto be posted around the room and referred to/added to throughout the unit.

Building on prior knowledge: Questions that the teacher might ask to assess students’ prior
knowledge.
 Pre-teaching:
Students should be familiar with the following vocabulary:
Biofuel
Biomass
Cell
DNA
Enzyme
Ethanol
Genetics
Hemicellulose
Lignin
Cellulose
Fermentation
Modification
Cell wall
Gene
Mutation
Students will build on ideas from previous units such as Mendelian Genetics, DNA, RNA and Proteing
synthesis as well as Cells. A powerpoint will be available (in the resource section) reviewing the above
vocabulary, as well as reviewing some basic concepts and introducing students to biofuels
Biomass referes to any organic substance and can range from vegetables or trees to solid wastes such as
paper and food based trash. The biomass can be converted to fuel by 2 main processes: biological
conversion and thermochemical conversion. Below is a diagram that highlights major steps to fuel
conversion:
Biomass
Biological
Conversion
Thermochemical
conversion
Pretreatment
(acid hydrolysis)
Enzymes
Sugars for
fermentation
Pyrolysis
(Upgrade)
Gasification
(Heat)
Electricity
Catalyst
Fuel
In biological conversion, the biomass is first treated using acid hydrolysis. The purpose of this step is to
break up the lignin and hemicellulose within the cell walls, which interfere with the enzymes' ability to
work on the cellulose. The enzymes break up the cellulose into sugars that can be used in fermentation.
After fermentation the ethanol produced is distilled and can be used as fuel.
In a thermochemical conversion, the biomass can be gasified or used in pyrolysis. Gasification
creates heat that can be used to generate electricity or heat a home. Pyrolysis requires burning at high
temperatures and pressure in the absence of oxygen. The product then needs to be upgraded to a more
useful fuel.
This activity looks at ways scientists are trying to “improve” the biomass in organisms such as corn, switch
grass and other plants. Scientists have mapped the genome of maize (corn plants) and are genetically
modifying the maize such that the cell wall contains higher amounts of cellulose than they have in the past.
The challenge that scientists face is figuring out what genes are involved in producing a cellulose-rich wall
and how they can create a healthy plant with this high cellulose wall and a reduction in lignin and
hemicellulose.
 Explore:
Lesson adapted from: US Department of Energy. “Cell Wall Recipe: A lesson in Biofuels”. Author:
Daniel Steever. Owner: National Renewable Energy Laboratory AND
http://docs.google.com/viewer?a=v&q=cache:BSwC8mfmDCkJ:hs.hpisd.org/uploads/45/f100873.doc+d
na+in+wheat+germ+extraction+lab&hl=en&gl=us&pid=bl&srcid=ADGEESjwrxqoDztIVagMgynEd4Eg
pG67MRY5sZuZLNumVnbjjo1UQEEn6Q-gyta8VdQYs4JFJeiDY-Q6Vca1iQHStBE0pWKgU3OcJRxDFcpghGKjROeUH5KbEY-5TZyUgadLsiEwaET&sig=AHIEtbQJ6cywRUrFxEwYNWHyd1EGnH2gA&pli=1
Wheat Germ DNA Extraction Lab
Background:
Remember that the four basic biological molecules that make up cells are nucleic acids,
proteins, carbohydrates, and lipids. We can actually separate these molecules using regular household
products. Our task for today is to extract DNA from the nucleus of wheat germ cells. Sounds tricky,
but in fact if we follow the procedure carefully we can do this.
We will be using a combination of household products to accomplish this. We will be using
hot water to speed up reactions and to assist in breaking up the biological molecules. We will also be
using a mild soap (Dawn or Ivory) to break up membranes. Remember that membranes are made of
lipids, commonly called fat, and Dawn “cuts grease out of your way.” Unfortunately, we do not have
a centrifuge in the classroom to “spin down” heavy molecules such as proteins and carbohydrates so
we will use a 70% mixture of rubbing alcohol to separate the nucleic acids from the solution. The
alcohol will create a precipitate with the DNA and after about 5 minutes the precipitate will float on
top bringing the DNA to the surface. The DNA will appear white and stringy. So why would we want
to do such a thing? Well DNA extraction is the first step to DNA “finger printing” or just about
anything else involving DNA experimentation.
HOW DOES IT WORK? DNA is present in all living things from bacteria to plants to animals. In animals,
it is found in almost all cell types: cheek, muscles, reproductive cells, hair roots, -- anything with a nucleus.
DNA is NOT found in Red blood cells because they lack nuclei. White blood cells do have a nucleus. DNA in
a cell is about 100,000 times as long as the cell itself. However, DNA only takes up about 10% of the cell's
volume. How can this be? This is because the DNA molecules fold themselves many times to pack
themselves in the cell's nucleus.
Each chromosome contains a single immense molecule of DNA that, in humans, has a length of up to 12
centimeters when stretched out! (look at 12 cm on ruler) As a matter of fact, all the DNA in one human cell
(on all 46 chromosomes) is about two meters long, yet fits into a cell nucleus which is 2-3 micrometers
(that's .000002 meters wide!). Yet, the DNA must still be in such a state as to allow for enzymes to replicate
the molecule or initiate the production of a protein. The 23 pairs of human chromosomes are estimated to
include about 100,000 genes.
WHEAT GERM
Wheat germ comes from wheat seeds. The “germ” is the
embryo, which is the part of the seed that can grow into a new
wheat plant. When wheat seeds are milled into white flour, the
wheat germ and wheat bran are removed, leaving only starch.
Wheat germ contains many nutrients while wheat bran consists of
fiber. Whole-wheat flour contains all parts of the wheat seed and
is therefore more nutritious than white flour while also providing
important fiber for digestion.
CHEEK CELLS
Cheek cells come from the inner lining of mouth or the check.
These cells are routinely shed and replaced by new cells.
As the old cells die, they accumulate in the saliva in the
mouth and can easily be collected by using mouthwash.
One might say “Spit Happens”.
ONION CELLS
An onion is used because it has a low starch content, which allows DNA to be seen. The walls of onion cells
are made of cellulose, which is a polysaccharide made of glucose. Cellulose provides a tough barrier that
protects the cell. In order to examine the contents of a plant cell,blending helps to burst open the cell's walls
and release contents. Onion cells also have membranes that envelop their contents. Cell membranes are made
of a double layer of lipids that allow the movement and transfer of
certain ions and substances in and out of the cell. Breaking down a
cell's membrane allows you examine the contents of the cell.
Detergents contain chemical compounds that can break down cell membranes.
Water temperature
The heat softens the phospholipids (fats) in the membranes that surround the cell and the nucleus.
It also inactivates (denatures) the deoxyribonuclease enzymes (Dnase) which, if present, would cut the DNA
into such small fragments that it would not be visible. Denatured enzymes and DNA unravel, loose their
shape, and thus become inactive. Enzymes denature at 60°C and DNA denatures at 80°C.
Detergent
Detergent contains sodium laurel sulfate, which cleans dishes by removing fats and proteins. It acts the
same way in the DNA extraction, pulling apart the fats (lipids) and proteins that make up the membranes
surrounding the cell and the nucleus. Once these membranes are broken apart, the DNA is released from the
cell.
Soap molecules and grease molecules are made of two parts:
Hydrophilic heads: which LIKE water and Hydrophobic tails which HATE water
Both soap and grease molecules organize themselves in bubbles (spheres) with heads outside to face the
water and tails inside to hide from the water.
When soap comes close to grease, it captures it,
forming a greasy soapy ball:
A cell’s membrane has two layers of lipid (fat) molecules with proteins between them:
When detergent comes close to cell, it captures the lipids & proteins & releases DNA:
Alcohol
The DNA released from the cell nucleus is dissolved in the water/detergent/wheat germ solution and cannot
be seen. DNA precipitates out of solution in alcohol, where it can be seen. Besides allowing us to see the
DNA, the alcohol separates the DNA from the other cell components, which are left behind in the water
solution. The alcohol also causes gases dissolved in the water to be released, which may be observed as
small bubbles.
Meat Tenderizer : acts as an enzyme to cut proteins just like a
pair of scissors. The DNA in the nucleus of the cell is molded, folded,
and protected by proteins. So, the enzyme (papain) cuts the proteins
away from the DNA. Papain also helps break down DNAase, an enzyme
that breaks down DNA)
(Not used in all of the DNA extractions)
DNA Extraction from Wheat Germ
Materials
Raw wheat germ – 1 level teaspoon
 Liquid detergent - 1 ml
 Ethyl Alcohol (95%) – 15 ml (COLD) on Ice
 50o – 60o Celsius tap water – 20 ml
 Hot plate with Beaker of Tap Water
 Thermometer
 2 - 50 ml beakers
 1 - Graduated cylinder (large)
 Glass stirring rod for stirring mixture
 Paper towel or Eye dropper – may be needed to remove foam
 Paper clip hook or wooden stick or spaghetti for collecting DNA
PROCEDURE:
1. Place 1 LEVEL teaspoon of raw wheat germ in a 50 ml beaker
2. Add 20 ml of hot (50-60 °C) tap water and mix constantly for 3 minutes.
3. Add 1 ml or (15 -18 drops) of detergent and mix gently for 5 minutes. DO NOT MAKE FOAM
4. Use a piece of paper towel or an eyedropper to remove any foam from the top of the solution.
5. BEFORE adding the alcohol, POUR the water/detergent solution into a clean beaker, leaving behind the
wheat germ.
6. Tilt beaker with the water/detergent solution at an angle.
SLOWLY pour 15 ml of COLD alcohol down the side so that
it forms a layer on top of the water/wheat germ/detergent solution.
Do not mix the two layers together. (DNA precipitates at
The water-alcohol interface (the boundary between the water and the alcohol). Therefore, it is
crucial to pour the alcohol very slowly so that it forms a layer on top of the water solution. If the
alcohol mixes with the water, it will become too dilute and the DNA will not precipitate.)
7. Let the beaker sit for a few minutes. White, stringy, filmy DNA will begin to appear where the water and
alcohol meet. You will usually see DNA precipitating from the solution at the water-alcohol interface as
soon as you pour in the alcohol. If you let the preparation sit for 15 minutes or so, the DNA will float to
the top of the alcohol.
8. You can usually get more DNA to precipitate from the solution by using one of the DNA-collecting tools
(paper clip hook) OR spaghetti to gently lift the water solution up into the alcohol. This allows more
DNA to come in contact with the alcohol and precipitate. Then use paper clip hook or a wooden stick or
spaghetti to collect the DNA.
9.
Place DNA on paper towel and air dry. FEEL IT. 0R
10. If time permits, place a small sample of DNA on a slide with coverslip; look at it with microscope.
Be sure to share results with all lab partners!!!

Explain:
DNA EXTRACTION
Group Names: ______________________
_____________________
______________________
Name________________ Table#_____
Date________________ Per._____
Teach
sign
READ NOTES ON BACK
1. List three things available to you that you might use for a DNA source besides wheat germ, onion, cheek
cells or split peas.
2.
List three things that would not be a DNA source.
3. What is the role/purpose of DNA in a cell?
4. a. Explain how DNA is contained in a cell.
b. Why does DNA extraction need to be performed in order to obtain DNA?
5. a. Describe what you saw happening in the beaker.
b. Describe the product that was obtained.
6. What is an Enzyme?
7. Why did you use detergent in the procedure, and how does it work? (see notes on back)
8. What possible benefits might be obtained by the ability to isolate the DNA of any organism?
9. Which “ingredient” (besides wheat germ,cheek cells, onions, or peas) do you think might have the most
effect on the amount of DNA you extract? __________________________________________
10. How can you test your Hypothesis? Describe an experiment to test your hypothesis.

Elaboration:
Results Questions:
1. What does the salt do? (gatorade) (Salt provides the DNA with a favorable environment; it contributes
positively charged atoms that neutralize the normal negative charge of DNA.)
2. What does the blender do? (help break down the cell walls)
3. When you mix the blended cell source with the soap, what is happening? (In the experiment, the
enzymes in the soap are breaking down the lipid molecules of the cell and nuclear membranes, releasing the
contents of the cell, including the DNA. These enzymes in the soap are what break down grease while
washing dishes.)
4. What does the alcohol do? Why does the DNA rise to the top after adding alcohol?
(DNA will not dissolve in this alcohol, so the DNA comes out of the solution, or precipitates. It is less dense
than water or cell scum--which is what settles to the bottom of the glass--so it floats up into the alcohol layer,
where you see it as a snotty, string-like substance, with small bubbles formed on it.)
5. If you try a seed food such as peas, there will be more protein residue in the liquid. Why? (Because
protein is stored in them for the nutrition of the new plant.)
6. Why can’t you see the double helix? (It is too small to be seen with the naked eye. What you extracted is
millions of strands of DNA.)
7. What part of the cell did the DNA come from? (99% is from the nucleus.)
BONUS:
1. If you did the experiment with both plant and animal cells, how would their DNA compare?

Evaluate:
Material List:
Strips of construction paper (3 different colors), glue, DNA strips (included below), poster board or butcher
paper, DNA decoder (included), scissors
DNA Strips:
Main Activities:
1. Engage students on day 1 by doing the Wheat Germ DNA Extraction Lab.
2. Mini-lecture on biofuels and plant biology (Plant biology should be a review.)
3. Tell students that they are genetic engineers and that they will be constructing a cell wall based on a
genetic code they have picked out with the DNA strips.
4. Distribute the DNA decoder sheet.
5. Have DNA strips cut out and placed in some sort of container and mix the strips up such that the
strips will be picked buy students randomly.
6. Have students choose 3 DNA strips from the container at random.
7. Students will now arrange the 3 strips to form a chain such that the 3 strips give 12 symbols in a row.
8. Tell students that every 3 symbols represents a gene and to use the decoder to figure out what their
DNA strand codes for.
9. Remind students what a genetic mutation is and review dominant and recessive genes.
Example:
Gene #1
Low lignin
Gene #2
High Cellulose
Gene #3
Gene #4
Medium Hemicellulose Low Lignin
10. Students can arrange their strips in anyway they wish. The target is to get low lignin and
hemicellulose and high cellulose. The first time it is fine if the student does not get the desired
combination, but students should work on arranging their DNA in the best possible combination. You
may allow students to switch out strips as many times as they wish to get the desired outcome.
However, the desired outcome is statistically based and the student may spend a great deal of time
trying to get the “correct” combination.
Issues:
If the student can’t get three genes for the three components of a cell wall they must “throw
out” one strip and replace it with something different from the DNA container and then find another
combination.
If the student gets a fatal mutation they must rearrange their strips or replace it with another.
(Many mutations scientists create to improve cell walls are fatal.)
If the student gets 2 genes for the same component (lignin, hemicellulose, or cellulose) the
student uses the gene that is most desirable.
11. Have students “build” their cell walls using strips of construction paper. Students should glue the
strips down in a way that cellulose is glued first, hemicellulose second, and lignin third. Students
should use a crisscross pattern so that all three layers are visible. The number of strips for low,
medium, and high are determined by the teacher. Suggestions: 3 strips = low, 6 = medium, 9 = high.
12. Now have students “improve” their cell wall buy changing the code. They can draw the new code or
pick out the same strips as before, cut out individual symbols and glue them down as their new code.
Repeat step 10 for the new code.
13. Students can display their work; do a write up, etc.
 Lesson Closure:
Assessment: Students will be asked to present their “cell walls” to the teacher one on
one as a “show and tell”.
Students will be asked to articulate the following:
1. What are the 3 principle components of plant cell walls?
2. How did you read your genetic code? Did you have to manipulate anything?
3. What was the ideal composition of the cell wall?
4. Why are high amounts of cellulose desirable?
5. What genetic modifications did you make to improve your cell wall?
6. Describe the process of converting biomass into ethanol in 5 steps.
7. What is a genetically modified organism?
8. How can biofuels help our society and environment?
Lesson Extension

Assessment Options:

Additional Resources:
1. Lesson adapted from: US Department of Energy. “Cell Wall Recipe: A lesson in Biofuels”.
Author: Daniel Steever. Owner: National Renewable Energy Laboratory
2. http://docs.google.com/viewer?a=v&q=cache:BSwC8mfmDCkJ:hs.hpisd.org/uploads/45/f100
873.doc+dna+in+wheat+germ+extraction+lab&hl=en&gl=us&pid=bl&srcid=ADGEESjwrxq
oDztIVagMgynEd4EgpG67MRY5sZuZLNumVnbjjo1UQEEn6Q-gyta8VdQYs4JFJeiDYQ6Vca1iQHStBE0pWKgU3OcJ-RxDFcpghGKjROeUH5KbEY5TZyUgadLsiEwaET&sig=AHIEtbQJ6cywRUrFxE-wYNWHyd1EGnH2gA&pli=1
***How to insert powerpoint