Inquiry Lesson Plan
Topic: DNA
Grade Level: 6-8
Time Allotment: three-four 30-45 minute sessions
Objectives: The students will be able to understand that chromosomes are structures in
the nucleus of a cell that carry genes. Also, students will understand that genes are
smaller units that contain the heredity code, DNA. Students will understand that the
genetic code is transmitted biochemically through molecules called deoxyribonucleic
acid. Finally, students will understand the structure of the DNA molecule.
Standards: Illinois Learning Standards
11.B.2 Plan and construct technological design, incorporating the safety and procedural
guidelines into the construction plan, or maximizing resource capabilities.
11.B.5 Communicate the results of design investigation presenting an oral and/or written
report, explaining the test of the scientific principle, using available technologies, relating
anecdotal and quantitative observations, or generating additional design modifications
which can be tested later.
12.A.2 Apply scientific inquiries or technological designs to explore the basic roles of
genes and chromosomes in transmitting traits over generations, describing how physical
traits are transmitted through sexual or asexual reproductive processes, charting pedigree
probabilities for transmissions, identifying examples of selective breeding for particular
traits, or analyzing how familiar human diseases are related to genetic mutations.
13.A.1a Use basic safety practices.
13.A.1c Explain how knowledge can be gained by careful observation.
Materials: For this activity you will need:
Day 1:
White Board, Markers, Pencils, Handout for Notes on DNA, Notebook Paper
Day 2:
• Two 24-inch pieces of fishing line
• Eight 2-inch pieces of blue chenille stems (pipe cleaners)
• Eight 2-inch pieces of green chenille stems
• Eight 2-inch pieces of purple chenille stems
• Eight 2-inch pieces of orange chenille stems
• Eighteen pieces of dried pinwheel pasta
• Sixteen pieces of dried ziti cut pasta
Day 3-4:
DNA activity sheet, white board, markers, Pencils, DNA notes
Inquiry Lesson Plan
Procedures:
Day 1: STEP 1 Think About it – Engagement
A) Check background knowledge of DNA.
What are chromosomes?
What are genes?
What is DNA?
How does DNA work?
B) Expository Learning of DNA
- Explain that organisms carry an elaborate blueprint containing the information
necessary to develop and maintain life. This “manual of instructions” is located in a
chemical molecule called DNA. DNA is found within a person’s genes. Genes are small
structures found in chromosomes, structures within the nucleus of cells.
-Tell students that DNA works something like the alphabet. While the alphabet has 26
letters, DNA’s “alphabet” has only four letters. These letters are guanine (G), adenine
(A), cytosine (C), and thymine (T). Just as the 26 letters of the alphabet can be used to
form millions of words for communication, DNA’s alphabet can be combined to form
codes with more than five billion combinations of G’s, A’s, T’s, and C’s. The differences
in these combinations result in differences among human beings.
C) Inquiry Learning of DNA
- Have children brainstorm some traits that are passed on from their parents. For example,
eye color, hair color, facial characteristics, etc. Write these down on a piece of paper.
- Partnering students up, have them discuss the traits that have been passed down to them
from their parents. Then have them discuss how these traits are passed down from one
generation to the next. The students should understand that genes are passed on from one
generation to the next. What is the makeup of the DNA in the genes? How are traits
passed on?
Day 2: STEP 2 Investigate – Explore
Part A.
The DNA molecule consists of two strands that form a double helix, a spiraling shape
much like a twisted ladder. The DNA molecule has a sugar component, a phosphate
component, and four different bases—adenine, thymine, cytosine, and guanine. To
help students understand how these components fit together to form DNA, have
each student make a model of DNA with fishing line, dried pasta, and differentcolored pipe cleaners.
Part B.
Have student gather the material for their DNA
• Two 24-inch pieces of fishing line
• Eight 2-inch pieces of blue chenille stems (pipe cleaners)
• Eight 2-inch pieces of green chenille stems
• Eight 2-inch pieces of purple chenille stems
Inquiry Lesson Plan
• Eight 2-inch pieces of orange chenille stems
• Eighteen pieces of dried pinwheel pasta
• Sixteen pieces of dried ziti cut pasta
Part C.
1. First, give each student 2 pieces of line, 18 pieces of pinwheel pasta, 16 pieces of ziti
pasta, and different-colored chenille stems (pipe cleaners). Explain that the pinwheel
pasta represents the sugar component, the ziti pasta the phosphate, and the chenille stems
each of the bases.
2. Tell students to start with the pinwheel pasta and alternate with the ziti pasta as they
thread the pasta on the line. On each line, they should string nine pieces of pinwheel pasta
alternating with eight pieces of ziti. Wrap the line around the final piece of pasta at the
end of each line so that the pasta does not fall off. After pasta has been strung on both
lines, each line should have a total of 17 alternating pieces of pasta. Have students lay the
two lines side by side.
3. Then give students the “code” for the chenille stems—the blue stem represents
adenine; the green stem, thymine; the purple stem, cytosine; and the orange stem,
guanine. Explain that the bases in DNA are found in pairs and that adenine always pairs
with thymine and cytosine always pairs with guanine.
4. Have students represent these base pairs with twisted chenille stems. First, have them
twist the eight blue stems and eight green stems together, making a total of eight bluegreen stems, about 2 inches long. Likewise, have them twist the eight purple and eight
orange stems together, making a total of eight purple-orange stems, about 2 inches long.
Students will find that the chenille stems twist together easily.
5. Now, have students create a “ladder” using the pasta lines as the sides and the twisted
chenille stems as steps. Beginning at the top, students should connect the two ends of a
twisted chenille stem to the top pasta pieces on the two lines. Then use a second chenille
stem to connect the next two pasta pieces directly across from each other. They should
continue building their ladder, one step at a time, until they have connected the bottom
two pieces of pasta. Remind them that they can place the twisted chenille stems in any
order. (The blue-green stems do not have to alternate with the orange-purple stems.)
After all the stems have been woven, the DNA model is complete.
Part D.
-Have students discuss their model in front of the class, discussing the shape of the DNA
molecule and reviewing the four bases of their model.
Day 2: STEP 3 Reflecting upon the Activity and the Investigation
Questions – Explain

How do the bases pair up in a DNA molecule? How does your model help you
figure this out?
Inquiry Lesson Plan


What differentiates one DNA molecule from another? How could you change
your DNA model to reflect changes among DNA molecules?
How do you think a DNA molecule makes an exact copy of itself? How does its
structure help it do so?
Day 3: STEP 4 Digging Deeper – Explain
Basic Structure
- Learning about basic characteristics of DNA we learned that DNA molecule consists of
two strands that form a double helix, a spiraling shape much like a twisted ladder. The
DNA molecule has a sugar component, a phosphate component, and four different
bases—adenine, thymine, cytosine, and guanine
- By making the DNA molecule with the pasta we learned that in DNA are found in pairs
and that adenine always pairs with thymine and cytosine always pairs with guanine.
More Understanding
Chromosomes
-The chromosome is a threadlike strand of DNA that is found in the nucleus of the cell.
These chromosomes come in pairs and normally there are 23 pairs of chromosomes (46
total chromosomes. Of those, 1 pair is the sex chromosomes (determines whether you are
Inquiry Lesson Plan
male or female, plus some other body characteristics), and the other 22 pairs are
autosomal chromosomes (determine the rest of the body’s makeup).Half of them come
from mom and half of them come from dad.
Genes
- A gene is a distinct portion of a cell’s DNA. Genes are coded instructions for making
everything the body needs, especially proteins. Human beings have about 25,000 genes.
Other Useful terms in understanding DNA
amino acids
Definition: The essential building blocks of life.
Context: Amino acids provide the structural components of cells and tissues.
chromosome
Definition: A structure found in the nucleus of cells.
Context: Chromosomes carry genes, smaller units that contain DNA, the code of life
cloning
Definition: To create progeny asexually.
Context: Dolly the sheep is recognized as the first mammal created through cloning
DNA
Definition: The genetic material contained in every cell and unique to each individual.
Context: DNA is responsible for the enormous possibilities for variability in the living
world.
enzyme
Definition: A complex protein that can catalyze biochemical reactions in the body.
Context: In addition to determining heredity, genes also carry the information needed for
constructing enzymes needed for essential biochemical reactions.
genetics
Inquiry Lesson Plan
Definition: The study of what genes are made of, how they work, and how they are
inherited.
Context: The field of genetics includes understanding how living systems grow and are
maintained during their life span and how they duplicate and pass on genetic material.
heredity
Definition: The transfer within a species of characteristics from one generation to
another.
Context: Heredity is responsible for how we look, what we are interested in, and in some
cases, what diseases we may get during our lifetime.
nucleotide
Definition: The basic structural unit of DNA.
Context: Each strand of a DNA molecule is a linear arrangement of nucleotides, which
are each composed of one sugar, one phosphate, and one nitrogenous base.
nucleus
Definition: A body found in most plant and animal cells that contains the genetic
material.
Context: Scientists were able to break the genetic code within the nucleus of cells.
polypeptide
Definition: A molecular chain of amino acids.
Context: Proteins are actually polypeptides, chains of more than two amino acids.
protein
Definition: A large, complex molecule made up of amino acids. Context: Human beings
can synthesize at least 100,000 different kinds of proteins.
Sum it up
We now know that chromosomes are found in the nucleus of cells that carry genes, which
hold DNA. DNA is the genetic material contained in every cell and unique to each
individual. Yesterday I had you discuss some common traits you have with your parents
and how these traits are passed down. Now you know that the chromosomes that are
passed on from your parents (23 from mom, and 23 from dad) hold DNA which is that
genetic material that carries the traits that you possess. DNA consists of two strands that
form a double helix, a spiraling shape much like a twisted ladder. The DNA molecule has
a sugar component, a phosphate component, and four different bases—adenine, thymine,
cytosine, and guanine.
Day 4: STEP 5 Understanding and Applying What You Have Learned Elaborate
The following is a puzzle that you could solve using the terms you learned through this
lesson.
Inquiry Lesson Plan
FUN WITH WORDS PUZZLE
Reference:
Puzzle Maker:
http://puzzlemaker.school.discovery.com/CrissCrossSetupForum.html
DNA
Across
2. A complex protein that can catalyze biochemical reactions in the
body.
3. A distinct portion of a cell’s DNA.
5. Genetic material contained in every cell and unique to each
individual.
9. A molecular chain of amino acids.
11. Structure found in the nucleus of cells.
12. A body found in most plant and animal cells that contains the
genetic material.
Down
1. The transfer within a species of characteristics from one generation
to another.
4. The basic structural unit of DNA.
6. Acid The essential building blocks of life.
7. To create progeny asexually.
8. The study of what genes are made of, how they work, and how they are
inherited.
10. A large, complex molecule made up of amino acids.
Inquiry Lesson Plan
Day 4: STEP 6 Inquiring Further –Elaborate / Evaluate
Understanding Further
Design and create a DNA model using materials of your own choice. Suggested materials
include stained glass, clay, beads, buttons, wood pieces, recycled materials, and food
items. They should include a key that explains what each item represents. After students
have completed their models, have them display the models in the classroom. This will
help students further understand the structure of the DNA because they will be setting
their own key for their items.
Inquiring Further
Genetic abnormalities occur quite frequently in newborn babies. For example, a child
might be born with Down Syndrome. What occurs in the genetic makeup of the child to
make them have this genetic disorder? Take the time to look up three genetic disorders
and give an explanation of what occurs in these children.
Day 4: STEP 7 Assessment –Evaluate
Objectives
Understand that
chromosomes are
structures in the nucleus
of a cell that carry genes
Location of Activity
Investigate
Digging Deeper
Understanding & Applying
Understand that genes are
smaller units that contain
the hereditary code, DNA
Investigate
Digging Deeper
Understanding & Applying
Understand that the
genetic code is transmitted
biochemically through
molecules called
deoxyribonucleic acid
(DNA)
Understand the structure
of the DNA molecule
Digging Deeper
Investigate
Digging Deeper
Understanding & Applying
Assessment Opportunity
Discuss with students to
check for understanding.
Check for understanding
through the application.
Discuss with students to
check for understanding.
Check for understanding
through the application.
Discuss with students to
check for understanding.
Students will be graded on
the structure of DNA that
they make. Also,
understanding will be
checked through discussion.
Inquiry Lesson Plan
Rubric
Delivery
Participation
Completeness
3
The student showed
enthusiasm while
presenting his/her
DNA molecule in a
clear and organized
manor
The student
preformed well
within their group.
He/she also
demonstrated his/her
knowledge about
previous vocabulary
and presented
creative
brainstorming ideas
The student’s DNA
was neatly completed
with all the correct
pieces in place. This
was done within an
allotted time period.
2
The student
presented his/her
DNA molecule in a
clear manor
1
The student
demonstrated very
little effort while
presenting his/her
DNA molecule.
The student tried to
work effectively
within the groups
and showed some
understanding of the
vocabulary
The student showed
lack of participation
within the group
and little class
discussion.
The student’s DNA
was completed with
all the correct pieces
in place.
The student’s DNA
was incorrect and
proper procedures
were not followed.
Reference:
Goldfein, W. (2008). Building a model DNA. Retrieved February 4, 2010, From
Discovery Education Web Site
http://school.discoveryeducation.com/lessonplans/programs/modeldna/#eva