SCIENCE.Grade7.PunnettSquares

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NCDPI – AIG Instructional Resource: Background Information
Resource Title: The Jamison Family Reunion—A Genetic Counselor’s View
Subject Area/Grade Level (s): Science/7
Time Frame: 1 class period (~60 minutes)
Common Core/Essential Standard Addressed:
ES 7.L.2.2 Infer patterns of heredity using information from Punnett Squares and pedigree analysis.
Additional Standards Addressed:
CC ELA W.7.3 Write arguments to support claims with clear reasons and relevant evidence.
Brief Description of Lesson/Task/Activity: Within the life science strand of 7th grade science, students focus on the patterns of inheritance and the
potential variation among offspring. In this task, students will act as genetic counselors for Nora, an individual who has learned of a genetic disorder that
affects her family after attending a reunion. Students will create a pedigree for the Jamison family based on provided information and use it to explain and
advise Nora. The real-world aspects of this lesson allow students to build meaningful connections and promote the development of 21st Century Skills.
Type of Differentiation for AIGs (include all that apply):
Adaptations for AIGs:
Content
x Process
x Enrichment
Extension
x Acceleration
x Product
Explanation of How Resource is Appropriate for AIGs: AIG students in the middle grades often are advanced in logic/reasoning skills. As a
result, they quickly grasp the concepts in Mendelian and Post-Mendelian genetics in the 7th grade Essential Standards for Science. To challenge
these students, it is necessary to provide opportunities for them to apply their understanding to a real-world situation. Explanatory writing is
essential in advanced courses (AP sciences, etc.), so any opportunity to develop this skill is beneficial to AIG students. Finally, self-assessment
using defined criteria further develops the metacognitive and evaluative/evidentiary reasoning ability of these students.
Needed Resources/Materials
 Engagement pedigree and questions
 Jamison Family Reunion background, info, and guided questions
 Genetic Counselor’s Advisory Report format and rubric
PUBLIC SCHOOLS OF NORTH CAROLINA State Board of Education | Department of Public Instruction
AIG ~ IRP Academically and/or Intellectually Gifted Instructional Resources Project
Sources:
 T-shirt outline from http://www.proteacher.net
 Teachers may choose to use existing materials within text ancillaries or from internet sites to generate the engagement pedigree and
questions or additional “Family Reunion” examples.
TEACHER NOTES: Prerequisite knowledge/skills are required. Students should have demonstrated success at interpreting pedigrees and
constructing/analyzing Punnett Squares. Students should also have an understanding of recessive and dominant genes in Mendelian genetics.
Sex-linked trait understanding is not necessary for this lesson unless the teacher incorporates such an example.
NCDPI AIG Curriculum Resource Outline
STAGE ONE: ENGAGE
The teacher should explain to students that they will be completing a RAFT activity. They will be assuming the Role of a genetic counselor who is
reviewing a family’s genetic history from a recently attended family reunion. The Audience will be the client, Nora (teacher). The Format will be
the development of a pedigree, Punnett Squares, and written analysis for the customer on the Topic--the presence of a genetic disorder in the
extended Jamison family.
If the students have not previously identified the relationships, type of trait (dominant, recessive, or sex-linked), and the genotypes of specific
individuals from a prepared pedigree, or constructed and analyzed Punnett Squares for genetic probability, it is strongly advised to provide that
instructional input at this time. If students have already demonstrated an understanding of these concepts and processes, then it is only
necessary to reference the need to use these skills at this time.
PUBLIC SCHOOLS OF NORTH CAROLINA State Board of Education | Department of Public Instruction
AIG ~ IRP Academically and/or Intellectually Gifted Instructional Resources Project
STAGE TWO: ELABORATE
Provide pairs of students with the Jamison Family Reunion t-shirt data set. After constructing the pedigree for this data, students should then
receive and answer guided questions about the visual representation of the data, such as:
1. Does this trait appear to be dominant, recessive, or sex-linked? What evidence from the pedigree supports your choice?
Teacher support questions for this question include:
• Clues if Dominant: Does every affected individual have an affected parent? Does one affected parent tend to produce more
than one affected offspring?
• Clues if Recessive: Does any affected individual have two parents without the trait? Do two affected parents always have
affected offspring?
• Clues if Sex-linked: Does no father –to-son transmission of the trait occur? Are males the great majority of those affected?
2. Based on your answer to Question #1, what is the only genotype possible for someone who has the trait if the dominant allele is
represented by T and the recessive is t? Explain.
3. Based on your answer to Q#1, what are the two possible genotypes for someone who does not have the trait? Explain.
Teacher support questions for these questions include:
• If students have not determined that this is a recessive trait, steer them back to the above clues.
• What two genotypes always produce the same phenotype in autosomal inheritance?
• What is the only genotype that produces a different phenotype in autosomal inheritance?
4. Based on your answers to Q#2 & Q#3, add genotype labels for the following six individuals: John, Jane, Daisy, David, Dawn, & Tami.
5. Based on Q#4’s genotype label additions to the pedigree, what must Sam’s genotype be? Why?
6. Based on Q#4’s genotype label additions to the pedigree, what could Sally’s genotype(s) be? Why?
Teacher support questions for this question include:
• Who has the trait according to your shading on the pedigree? What must their genotype be as a result of the type of trait?
• For John and Jane to have a son (David) with the trait, what must Jane’s genotype be to provide him with two recessive alleles?
• For Daisy and Dawn to not have the trait, but have received an allele from their father who does, what must their genotypes be?
• For Daisy and Sam to have a daughter (Tami) with the trait, but to not have the trait themselves, what must Sam’s genotype be?
• Since David has the trait, but none of his or Sally’s children do (nor does Sally herself), Sally is most likely to be which
genotype? What other genotype is also a possibility even though it has not yet resulted in an offspring with the trait?
Students will then be challenged to determine the probability of this trait occurring in Nora’s future offspring based on the statement:
7. Nora decided to be genetically tested and learned she is a hybrid for this trait. Using Punnett Squares and their analysis, explain the
probability that her offspring could have this trait.
Teacher support questions for this question include:
• Now that you know Nora’s genotype, who else’s genotype do you need to know?
• What genotypes are possible for Nora’s future husband?
• Will you need to construct more than one Punnett Square to represent the possible combinations of Nora and her future husband?
• How do you determine the percentage probabilities from a Punnett Square?
• Based on your Punnett Squares, could Nora’s offspring ever have the trait? Under what circumstances?
PUBLIC SCHOOLS OF NORTH CAROLINA State Board of Education | Department of Public Instruction
AIG ~ IRP Academically and/or Intellectually Gifted Instructional Resources Project
STAGE THREE: EVALUATE
The teacher should decide if the assessment will be prepared by the partners together or if each partner will write his/her own client analysis.
The format and scoring rubric should be provided to students at this time.
Using the “Genetic Counseling Analysis Form GC-1” format, students should provide the client (Nora/teacher) with the following information:
-an accurately completed pedigree of her extended family with generation, name, and genotype labels (where appropriate)
-a clear and concise explanation of the genetic trait type and which genotypes result in which phenotypes as a result
-a clear and concise explanation of the inheritance patterns in her extended family with examples
-a clear and concise explanation of the client’s probability of offspring with the trait, with examples from Punnett Square analysis
A 4-point rubric is suggested for the assessment of each segment of the GC-1 form,
4= entirely accurate with appropriate explanation and examples clearly and concisely written
3= entirely accurate with appropriate explanation and examples, but lacking some organization or focus in writing
2= some issues with accuracy, appropriate explanation, and examples and/or lacking in organization and focus in writing
1= significant issues with accuracy, explanation, and examples and/or confusing to the reader
TEACHER NOTES: Preparing multiple “Family Reunion” scenarios would allow students to switch data and explanations to allow for peerassessment and/or continued experience/exposure to these concepts. To add another level of difficulty, consider using pedigrees that show two
families’ full pedigrees and a marriage between the two in the last or next to last generation.
PUBLIC SCHOOLS OF NORTH CAROLINA State Board of Education | Department of Public Instruction
AIG ~ IRP Academically and/or Intellectually Gifted Instructional Resources Project
PUBLIC SCHOOLS OF NORTH CAROLINA State Board of Education | Department of Public Instruction
AIG ~ IRP Academically and/or Intellectually Gifted Instructional Resources Project
PUBLIC SCHOOLS OF NORTH CAROLINA State Board of Education | Department of Public Instruction
AIG ~ IRP Academically and/or Intellectually Gifted Instructional Resources Project
Genetic Counseling Analysis Form GC-1
PUBLIC SCHOOLS OF NORTH CAROLINA State Board of Education | Department of Public Instruction
AIG ~ IRP Academically and/or Intellectually Gifted Instructional Resources Project
Prepared by: _______________________________________
Jamison Family Pedigree:
PUBLIC SCHOOLS OF NORTH CAROLINA State Board of Education | Department of Public Instruction
AIG ~ IRP Academically and/or Intellectually Gifted Instructional Resources Project
Explanation of Genetic Trait (use Q#1-Q#3):
Explanation of Genetic Inheritance of Trait (Use Q#4-Q#6):
Explanation of Probability of Client’s Offspring Genotypes/Phenotypes (Use Q#7):
PUBLIC SCHOOLS OF NORTH CAROLINA State Board of Education | Department of Public Instruction
AIG ~ IRP Academically and/or Intellectually Gifted Instructional Resources Project
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