Unit Overview:

Students develop an understanding of the structural relationships between DNA, genes, chromosomes, and proteins in lessons that include videos, discussions, the creation of a skit, and a telephone game-style activity that demonstrates how small point mutations can have dramatic effects on proteins and thus the traits of an organism (MS-LS3-1).  Students use the mutated traits from this activity in a culminating design challenge where they design and build a model of the organism exhibiting the mutated traits according to a set of criteria and constraints (MS-ETS1-2).

Educational Outcomes:

  • Lesson 1: Students create and perform a skit that describes the structural relationship between DNA, genes, chromosomes, and proteins
  • Lesson 2: Students identify point mutations in replicated gene sequences, associate them with organism traits, and discuss implications in terms of proteins
  • Design Challenge: Student groups design and build models of an organism having mutated traits and compare their models against a set of criteria and constraints

 


STEAM INTEGRATION

The skit developed during Lesson 1 provides an opportunity to blend performing arts with science content that is foundational to understanding how mutations can result in altered proteins and traits in an organism (MS-LS3-1).  Lesson 2 builds on the first lesson by allowing students to think critically about the significance of small changes to an organism’s gene sequence, leading from a molecular change to potential macroscopic trait changes in an organism.  The Design Challenge blends these genetics concepts with the design process in that students incorporate mutated traits into a model built according to specific criteria and constraints as engineers do in their practice.  The student groups build models of an agreed upon organism and follow the same general design rules, allowing them to make meaningful comparisons between group designs (MS-ETS1-2).

Click on the “+” icon to open each section

Unit Materials

  • RAFT Makerspace-in-a-box
    • Various adhesives, connectors, and fasteners (e.g., paperclips, binder clips, thread, yarn, adhesive foam pads, wooden stir sticks, straws, spoons, pipettes, labels & stickers, rubber bands, etc.)
    • Materials (e.g., laminate samples, dust covers, foam pieces, deli containers, fishboard, cardboard tubes, plascore scraps, posters, shower caps, scrap materials, cards, etc.)

Design Thinking Overview

Our design thinking units have five phases based on the d.school’s model. Each phase can be repeated to allow students to re-work and iterate while developing deeper understanding of the core concepts. These are the five phases of the design thinking model:

EMPATHIZE: Work to fully understand the experience of the user for whom you are designing.  Do this through observation, interaction, and immersing yourself in their experiences.

DEFINE: Process and synthesize the findings from your empathy work in order to form a user point of view that you will address with your design.

IDEATE: Explore a wide variety of possible solutions through generating a large quantity of diverse possible solutions, allowing you to step beyond the obvious and explore a range of ideas.

PROTOTYPE: Transform your ideas into a physical form so that you can experience and interact with them and, in the process, learn and develop more empathy.

TEST: Try out high-resolution products and use observations and feedback to refine prototypes, learn more about the user, and refine your original point of view.

The Design Thinking Process | ReDesigning Theater. (n.d.). Retrieved April 2, 2016, from http://dschool.stanford.edu/redesigningtheater/the-design-thinking-process/

STEAM Integrated Standards

NGSS MS-LS3-1: Develop and use a model to describe why structural changes to genes (mutations) located on chromosomes may affect proteins and may result in harmful, beneficial, or neutral effects to the structure and function of the organism.

NGSS MS-ETS1-2: Evaluate competing design solutions using a systematic process to determine how well they meet the criteria and constraints of the problem.

Suggestions for pacing and differentiation

Lessons 1 and 2 can be taught as stand-alone activities that address the organization of life, moving from the microscopic to the macroscopic scale.  The design challenge can be taught as a reverse engineering lesson where students are given specific traits and then research and identify the ones caused by point mutations.  They can then build the organism as it would be had those point mutations not occurred.

Lesson Overview

Students develop an understanding of how a cell’s DNA is tightly packed to form chromosomes in the nucleus.  This helps students understand that genes, segments of the DNA that code for proteins, are located on the chromosomes (MS-LS3-1).  Students watch videos to learn the roles and relationships between DNA, genes, chromosomes, and proteins and then develop and perform skit that demonstrates their knowledge of these relationships.

Essential Questions:

  • What are the relationships between DNA, genes, chromosomes, and proteins?

LESSON PROCEDURE:

  1. Students watch the videos in the External Resources section and record information in the Maker Journal (see Student Directions below).
  2. Students plan out a short skit to demonstrate their understanding of the relationships between DNA, genes, chromosomes, and proteins.  They assign roles to each member of the group, create dialogue, plan different movements, and develop props as needed.
  3. Students record the skit plan in the Maker Journal.

Sample Student Directions (Click + to open)

Sample teacher and student dialog.

T: What do you know about genes?  What about proteins?  How are genes and proteins related?  How does DNA factor in the conversation?”

S: “Genes contain proteins!”  “DNA codes for genes, which define our traits.”

T: “We’ll explore these ideas by viewing some videos to gather information, and then we will develop a skit.  A skit is a performance intended to inform people on a topic.  Your topic for the skit is the relationships between DNA, genes, and chromosomes, which also includes proteins.  In other words, your performance will go from DNA to chromosome!”

S: “Why do we need to know this?  What comes next?”

T: “Great questions.  This information will help us better understand the role of mutations in changing genes, which code for proteins.  We’ll cover that in the next lesson!”

dl-student


Concept Quick Reference (Click + to open)

 

DNA: A long macromolecule that is the main component of chromosomes.  It contains two molecule chains, or strands, made of nucleotides.  Each nucleotide contains a sugar molecule, a phosphate molecule, and a nitrogen-containing molecule called a nitrogenous base.  There are four nitrogenous bases: adenine (A), thymine (T), cytosine (C), and guanine (G).  The nitrogenous bases on each strand bond to each other, forming the familiar ladder-like structure that is twisted (double helix).

Genes: Segments of DNA that contain the code for a specific protein that functions in one or more types of cells in the body.  They are the basic units of heredity, where traits are passed from parent organisms to offspring.

Chromosomes: A structure composed of DNA tightly wrapped (super coiled) around protein molecules.  Chromosomes typically contain hundreds to thousands of genes.  Human cells contain 23 pairs of chromosomes, for a total of 46 chromosomes.

Proteins: Organic molecules constituting a large portion of the mass of every life form and necessary in the diet of all animals and other non-photosynthesizing organisms.  They are composed of 20 or more amino acids linked in a genetically controlled linear sequence into one or more long polypeptide chains (see below).  Examples of proteins include collagen for supportive tissue, keratin for fingernails and hair, hemoglobin for transport, antibodies for immune defense, and enzymes for metabolism.

DNA to Chromosome

 

Protein Structure (Primary)

Lesson Materials

Tech

  • Computers or mobile devices
  • Internet Access

Maker Journal Pages

dl-student

Teacher Notes

Encourage students to pause videos as needed.  They may find it useful to draw images or animations displayed in addition to writing down notes.

Learning Targets

  • Students will be able to describe the relationships between DNA, genes, chromosomes, and proteins

Assessment

Student Self Assessment

Students confirm their dialog contains enough detail to fully explain their assigned role in the skit

Peer Assessment

Student groups provide constructive feedback to performing groups to enhance the message in the skits

Teacher Assessment

Listen for proper usage and description of these key words in the skit dialogue: DNA, gene, chromosome, protein.  Provide feedback to clarify logic in moving from DNA to chromosome, or from chromosome to DNA.

Lesson Overview

Students groups conduct an activity where they read a DNA pattern and must quickly assemble the complementary sequence correctly.  After a few rounds of faster and faster assemblies, students analyze the resulting sequence and identify mistakes (mutations).  The mutations will correspond to changes in traits of a known organism, which students will explain in terms of changes in proteins.

Essential Questions:

  • What is a genetic mutation?
  • How do mutations result in changes in proteins?
  • How do changes in proteins result in changes in an organism’s traits?

LESSON PROCEDURE:

  1. Allow students to form groups of three.
  2. The groups write the letters for the nitrogenous bases onto index cards, one base per card, so they have a supply for the activity.
  3. Group members choose one of three possible roles: 1) Reader – reads the DNA template sequence, 2) Supplier – holds and distributes complementary nitrogenous base pairs, and 3) Assembler – puts complementary bases in the order communicated by the reader.
  4. Briefly survey the class an agree on an organism of interest, or specify for the class the organism from which the DNA is from in this activity (e.g., duck, lizard, bird).  Make and display a trait key for the organism (see example below).
  5. Write a 10-15 base DNA sequence on a strip of receipt tape (example: ATTGCTATC …).  Make the sequence longer or shorter if needed.  Make 3-4 different sequences in the same manner.  Hold onto the DNA sequences.
  6. The activity begins with the reader from each group coming up to you one at a time and viewing the DNA sequence for 30 seconds.
  7. The reader verbally communicates the sequence to the supplier in the group.  The supplier pulls the bases needed to form complementary base pairs with the sequence and passes them to the assembler.
  8. The assembler puts the bases in the correct order, forming a complementary gene sequence (1 minute).
  9. Students write the complementary sequence in the Maker Journal page for the round.
  10. The reader then confirms and records the original template sequence, which is shared with the group so they can all record it in the Maker Journal page.
  11. Repeat the process for three more rounds, using the other template sequences on receipt tape, but reduce the time given to the assembler to form the complementary sequence.
  12. Students analyze the sequence written in the Maker Journal, comparing it to the template sequence and looking for the mutations in the sequence.  They note where the mutations occurred along the strand (see example below).
  13. Students use the trait key to identify the traits associated with the mutations and write them in the Maker Journal.
  14. Students watch a video on the relation between mutations and proteins in organisms.
  15. Discussion: Students discuss possible answers to the essential questions.

EXAMPLE: Template to Complementary Sequence

EXAMPLE: Finding Mutations in the Sequence

 

EXAMPLE: Trait Key

 

 

 

 

 

 

Sample Student Directions (Click + to open)

Sample teacher and student dialog.

T: “Today we are learning how to model point mutations, those mutations affecting one nucleotide in a gene sequence.  The model will help us understand how mutations lead to changes in proteins and and traits.”

S: “What will the model look like?”  “What will we do after using the model?”

T: “The model is a card activity where you practice base-pairing rules (A-T, G-C) and create a complementary gene sequence, only the procedure will involve specific roles for each member of your group and will happen really fast!  Afterwards, you will identify where the mutations are and then use a key to determine the trait(s) the mutation causes in the organism.”

S: “Let’s use lizards as the organism!”  “If we are keying out traits, what will we do with them on the organism?”

T: “We will soon be doing a design challenge where you build the organism with the mutated traits.  Be sure to record your results in the Maker Journal page.”

Students record their observations in the Maker Journal page (click button below).

dl-student


Concept Quick Reference (Click + to open)

A point mutation is a genetic mutation caused by the insertion, deletion, or substitution of a single nucleotide base in a sequence of DNA or RNA.  Point mutations have a variety of effects on the downstream protein products during protein synthesis.  The consequences of point mutations for the organism are moderately predictable based upon the specifics of the mutation, ranging from benign to catastrophic in regards to protein production, composition, and function.

Point mutations usually take place during DNA replication when one double-stranded DNA molecule creates two single strands of DNA.  Each strand is a template for the creation of the complementary strand.  A single point mutation can change the whole DNA sequence.  Changing one nitrogenous base may change the amino acid that the nucleotide code for and this changes the structure and function of the resulting protein (proteins are made of amino acid chains).  Point mutations may arise from spontaneous mutations that occur during DNA replication.  The rate of mutation may be increased by mutagens.  Mutagens can be physical, such as radiation from UV rays, X-rays or extreme heat, or molecules that misplace base pairs or change the DNA’s shape.  (Source: Wikipedia)

The graphic below shows a specific point mutation called a missense mutation.  This occurs when there is a replacement of  a single nucleotide, resulting in a completely different amino acid during protein synthesis (histidine becomes proline in the graphic).  The result is a malfunctioning protein which could have neutral, beneficial, or dangerous effects on the organism.

Lesson Materials

Building Materials

  • Index cards or equivalent
  • Markers
  • Receipt tape or paper strips
  • Scissors

Tech

  • Computers or mobile devices
  • Internet access

Maker Journal Pages

dl-student

Teacher Notes

This activity does not cover the full process of transcription and translation of genetic information from DNA to mRNA to protein

The trait key can contain hypothetical traits to illustrate the idea that mutations that change only one nitrogenous base can have a major impact on the resulting protein and thus can alter the traits of an organism.

Learning Targets

  • Students will be able to describe how (point) mutations lead to changes in proteins and traits in an organism

Assessment

Student Self Assessment

Student groups can practice pulling complementary base cards for a longer gene sequence

Peer Assessment

Student groups discuss and compare their Maker Journal pages focusing on the traits caused from the mutations created in by group

Teacher Assessment

Provide students with a long gene sequence (20-30 bases) and give them a minimal amount of time to quickly (15-20 seconds) write the complementary sequence and identify point mutations along the sequence.  Review student work.

Design Challenge Overview

In the culminating project, students work in teams and ideate, prototype, and test a model of an organism agreed upon by the class in the previous lesson for which they identified mutated traits.  They continue to iterate until the team agrees that the organism model meets a set of defined criteria and constraints.  They present the models to their peers and describe how point mutations led to the mutated traits represented in the model.

Essential Questions:  

  • How can we build a model of an organism to demonstrate that single point mutations can lead to changes in an organism’s observable traits?
  • How can such a model be used to describe how point mutations lead to changes in proteins that then lead to changes in traits?

Lesson Procedure

Introduce the Design Challenge (Click + to open)

Sample student & teacher dialog.

T: “We studied and performed a skit to describe the relationship between DNA, genes, and chromosomes.  Remember that genes code for proteins.  We also learned about the possible effects that single point mutations can produce in an organism.  Today we will build models of the organism we focused on in the point mutation activity, and it will have the mutated traits you identified in the complementary base-pair sequences you assembled.”

S: “How do we know what the model should include?  For example, if we focused on cats, how many cat features need to be in the model?  What do we use to build it?”

T: “These are great questions.  We’ll review the basic rules for the models, which we call criteria and constraints.  We’ll review these together so everyone understands what we need to see in the models.”

S: “What will we do after we build the models according to the criteria and constraints?”

T: “You will present them to the class.  Describe the main features of your model, spending more time on the parts that represent the mutated traits you keyed out in the previous lesson.  Describe how the traits ware due to changed proteins caused by mutations.  You should leverage everything we did so far, including the web resources we used.”

Criteria & Constraints

Review the criteria and constraints with students.  Engineers design things using some rules about how the designs must behave or work.  These rules are called criteria.  Engineers can run out of materials, money, time to build, or space in which to build something.  In other words there are limits on how something can be built.  These limits are called constraints.  The criteria and constraints for this challenge are below.

 

Criteria (design requirements) Constraints (design limitations)
  • Model is recognized as the organism of interest (as close as possible)
  • Model includes at least one mutated trait (due to point mutation)
  • Mutated trait should be easily visible (this can be exaggerated to make it stand out, especially if it is a small feature)
  • Model stays intact (does not fall apart!)
  • Model is portable
  • Model must be built with only the materials provided
  • Model must be completed and tested in the given time period
  • Model must include at least 8 different materials NOT including fasteners or adhesives
  • Model must not be secured to the ground in any way

 


Ideate

Student teams conduct a brainstorm where they explore different ways of representing the organism of interest, keeping the criteria and constraints in mind.  They should convey ideas verbally, written, or in drawing form, recording ideas in the Ideate Maker Journal page (see Student Directions).  Students may revisit this ideate step at any point while designing the model.

Ideate: Sample Sample Student Directions (Click + to open)

T: “Before you build your models you need to come up with ideas on how to model certain parts of the organism.  Brainstorm with your team.  Remember to consider all possible ideas and avoid judging ideas at first.  Once you have lots of ideas on how to build it, select the ideas that seem easiest to implement and build on those ideas.”

S: “Can we look at the materials to help think of ideas?  I’m a visual person.  What should we write down?”

T: “Yes!  The materials can help guide your thinking of ideas.  Make sure you record all ideas in the Maker Journal page.  This way all ideas are accounted for and can be useful if you return to this step while prototyping.”

S: “Let’s get started!”

dl-student


Prototype

Student teams start building their organism models according to the defined criteria and constraints.  They ensure the model includes the mutated traits derived from the activity in the previous lesson and looks as realistic as possible given the materials provided.  The first prototype will likely not be perfect and after testing the model against the criteria and constraints, students will revisit this step in the design process multiple times and reiterate.

Prototype: Sample Student Directions (Click + to open)

T: “Now that you have lots of ideas that your team decided would be a good first approach, start building your models.  It is okay to think of more ideas (ideate) as you prototype.  This often happens when you are handling materials.  Use the Prototype Maker Journal page (click button below) to guide your thinking, sketch your model, etc.”

S: “How will we know when the first prototype is complete?  What if we can’t get the main features of the organism to look realistic in the model.”

T: “It is okay of the model is not perfect and does not look 100% like the real organism.  You are trying to get as close as you can given what you have to build with.  For example, we know that duck feet do not look like forks, but using forks as duck feet would be close enough to convey the idea.  After your team confirms that the model meets all of the criteria and constraints through testing and reiterating, you can say you are done.”

S: “When do we officially start the testing process?”

T: “You can start testing as soon as you believe the model has all of the required features to make it resemble the organism having the mutated traits you identified earlier in this unit.  I will not have a separate block of time for testing and will not say “GO!”  Your team has to decide when it’s time to test the prototype.”

dl-student


Test your Design

Students evaluate their organism models to ensure they represent the organism and include any mutated traits identified in the previous lesson.  They use the criteria and constraints checklist provided in the Test Maker Journal page.  As they work through this process they may need to generate new ideas (ideate) and modify their models (reiterate) as needed.

Test: Sample Student Directions (Click + to open)

T: “When your team agrees it is time to test the model, use the checklist provided in the Test Maker Journal page (click button below) to evaluate it, ensuring it meets the criteria and constraints.”

S: “Can we use the checklist many times?  What if we need to make more changes to the model?”

T: “That’s okay!  You can run through the checklist as many times as you need to arrive at a great model.  Along the way you may identify things that need to be fixed, changed, or removed completely.  When you do this you are generating new ideas (ideating) and making the necessary changes or modifications to the model, creating newer versions of the model.  This is why we often use the term “reiterate.”  It means to create new or improved versions of a product.”

S: “I like that we can have lots of chances to get it right!”

dl-student

 

Concept Quick Reference (Click + to open)

The design process allows students to learn and practice several 21st century skills such as the four C’s (critical thinking, collaboration, communication, creativity) as well as the 5 E’s (engage, explore, explain, extend, evaluate).  The skills are practiced during the key design process stages called out in this design challenge lesson.  For example, communication and collaboration naturally occur while students brainstorm ideas for the models in the ideate phase.  As students prototype, they think critically about ways to shape and manipulate materials to closely resemble the organism they are modeling.  This demonstrates the overlap and connections between the stages of the design process and the skills students develop as they experience effective STEAM-focused learning experiences.  The definitions of the design process phases and examples from this unit are provided below to guide your thinking in designing more STEAM lessons.

The Design Process

Empathy – An understanding of multiple perspectives on a question, problem, or task.  Students develop empathy on the effects of mutations on proteins and traits through a skit where they kinesthetically model DNA, genes, and chromosomes.

Define – To learn and practice underlying concepts, vocabulary, and skills pertaining to a larger idea or task.  Students learned that point mutations can have a large impact on the proteins produced, and thus the traits, of an organism even though they are caused by mistakes in as few as only one DNA nucleotide.  They do this by playing a telephone style game where point mutations are highly likely to be introduced in the genetic code.

Ideate – Students engage in a brainstorm session in order to generate ideas for the models developed in this design challenge lesson.  They must keep criteria and constraints in mind as they come up with potential ideas for addressing the essential questions.  Students brainstorm ideas for building the organism model so that it includes identified mutations and normal traits on the organism.

Prototype – A version of a design solution that is tested against the criteria and constraints defined for the problem.  Prototyping involves developing several versions in a process called iteration.  Students use a criteria and constraints checklist to evaluate their models.

Test – To evaluate the performance of a design solution against the defined criteria and constraints for the design problem or question(s).  In this regard, the word “test” does not mean to evaluate the model’s ability to perform a job or demonstrate how to achieve a task.  In this lesson, the test is to have all of the criteria represented in the model and to adhere to the design constraints.  This makes the checklist a simple tool for students to use because the model either meets the criteria and constraints or it does not, in which case the students continue to iterate.

Design Challenge Materials

Building Materials

RAFT Makerspace-in-a-box

  • Various adhesives, connectors, and fasteners (e.g., paperclips, binder clips, thread, yarn, adhesive foam pads, wooden stir sticks, straws, spoons, pipettes, labels & stickers, rubber bands, etc.)
  • Materials (e.g., laminate samples, dust covers, foam pieces, deli containers, fishboard, cardboard tubes, plascore scraps, posters, shower caps, scrap materials, cards, etc.)

Tech

  • Computers or mobile devices
  • Internet access

Teacher Notes

Position all materials in a location that provides equitable and safe access to students.  Clarify that student groups are not supposed to take all of a particular material for their model.  Encourage creativity but remind students to make sure the mutated traits can be easily identified and called out in the models.

Active Classroom

Tips for success in an active classroom environment:

Communication is critical in the design process. Students need to be allowed to talk, stand, and move around to acquire materials. Help students become successful and care for the success of others by asking them to predict problems that might arise in the active environment and ask them to suggest strategies for their own behavior that will ensure a positive working environment for all students and teachers.

Practice and predict clean-up strategies before beginning the activity. Ask students to offer suggestions for ensuring that they will leave a clean and useable space for the next activity. Students may enjoy creating very specific clean-up roles. Once these are established, the same student-owned strategies can be used every time hands-on learning occurs.

Learning Targets

  • Students will be able to build and compare organism models according to a set of criteria and constraints
  • Students will be able to use their models to explain how mutations can result in proteins and traits that are beneficial, harmful, or neutral in an organism

Assessment

Student Self Assessment

Student groups review their Maker Journal entries and identify areas where models can be improved.

Peer Assessment

Student groups discuss and compare their models in regards to genetically-mutated traits that benefit, harm, or have no effect on the organism

Teacher Assessment

Provide suggestions for improving the models, emphasizing reiteration, and ask questions to check for understanding that mutations in gene sequences lead to changes in proteins, which can lead to changes in chromosomes and thus traits.