Name _____________________________________________
ActActivity:
Activity: Take a Class Survey
Goal: To determine if traits controlled by dominant alleles are more common than traits
controlled by recessive alleles.
.
Background Information:
Gregor Mendel was curious about the physical characteristics, or traits, of pea
plants. The passing of traits from parents to offspring is called heredity. Mendel’s work
was the foundation of genetics, the scientific study of heredity.
From his work, Mendel reasoned that individual factors, one from each parent
controlled the inheritance of traits. Today, scientists call the factors that control traits
genes. The different forms of a gene are called alleles.
Individual alleles control the inheritance of traits. Some alleles are dominant,
while other alleles are recessive. A dominant allele is one whose trait always shows up
in the organism when the allele is present. A recessive allele is masked, or covered up,
whenever the dominant allele is present. A trait controlled by a recessive allele will only
show up if the organism inherits two recessive alleles for the trait.
Human traits are controlled by dominant and recessive alleles, causing many
different combinations of traits among a group of people. (Information is from Prentice
Hall: Science Explorer.)
Materials: mirror, data collection chart
Procedure:
Part 1: Dominant and Recessive Alleles
1. What I Know: Write a hypothesis that states whether you think certain traits
controlled by dominant alleles occur more often than traits controlled by recessive
alleles.
[Example: I predict that traits controlled by dominant alleles are (more common, less
common, equally as common) as traits controlled by recessive alleles.]
My hypothesis is:
2. See page 86 in your text book for pictures showing the following traits.
A. Free ear lobes vs. attached ear lobes
B. Hair on fingers vs. no hair on fingers
C. Widow’s peak vs. no widow’s peak
D. Curly hair vs. straight hair
E. Cleft chin vs. smooth chin
F. Smile dimples vs. no smile dimples
3. For each of the traits listed in the data table, determine which trait you have. Circle
that trait on your data table.
4. On the data table include the data for your group.
5. The teacher will ask you for your group data so that we can complete the class data
column on the chart below.
Dominant and Recessive Alleles
A. Circle your traits on the table below.
B. Record the results from your group and record them in the group data column.
C. Record the class results from the white board in the class data column below.
Trait 1
Dominant
Traits
Group
Data
Class
Data
Trait 2
Recessive
Traits
A Free earlobes
Attached earlobes
B Hair on fingers
No hair on fingers
C Widow’s peak
No widow’s peak
D Curly hair
Straight hair
E Cleft chin
Smooth chin
F
No smile dimples
Smile dimples
Group
Data
Class
Data
Part 2: Are You Unique?
1. Look at the Circle of Traits on the last page of this handout. All the traits on your
data table appear in the circle.
2. Place the eraser end of your pencil or your finger on the trait in the small
central circle that applies to you - either free ear lobes or attached ear lobes.
2. Move your eraser onto the next description that applies to you. Continue using your
eraser to trace your traits until you reach a number on the outside rim of the circle.
My number on the circle of traits: ____________
Questions:
1. The traits listed under “Trait 1” in the data table are controlled by dominant alleles.
The traits listed under “Trait 2” are controlled by recessive alleles.
Which traits controlled by dominant alleles were shown by a majority of students?
Were more dominant or recessive traits shown by students in the class?
2. If we increased the number of traits on the Circle of Traits from the five we observed
to say 15 or more, what would happen to the chance of someone in the class
sharing all the same combination of traits?
3. How does your data support the hypothesis you proposed in step 2?
Explain your answer with examples from this activity.
What I Wonder: Pose a ‘why” of “how” question about what you still wonder about this
topic.
Name _____________________________________
Lab. Take a Class Survey
Date _____________
What I Learned: Complete the following table to explain what you learned from this
activity. Use your CER Rubric to guide your writing.
Goal: State the goal of this Goal:
Question: Change the statement for
lesson.
the goal of the lesson into a question.
Claim: Describe what you
learned from this
investigation and be sure it
relates to the goal of the
lesson.
Evidence: Provide
evidence from the
investigation to support
your claim. Use the
information from your data
table and the circle of traits
you collected to support
your claim. Be specific!
Reasoning/Explanation:
Explain how the evidence
connects to the claim.
Provide the scientific
principles that support your
evidence and claim.
What’s the “science” that
supports your results/?
Conclusion: Supports the
reasoning or explanation,
reiterates the claim, and
extends the claim by
including a connection to
self, text or world.
Why is this important to
you?
Name __________________________________
CER. Take a Class Survey
Date__________
Directions: Use your experience from the lab activity, Take a Class Survey and
write a CER narrative that includes a goal, a claim, evidence to support your claim,
reasoning that connects your claim with the evidence, and a conclusion that contains
a connection to self, text, media or world.