Are You Suprised ? s42

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 Group Class Trait 2 Group Class Dominant Data Data Recessive Data Data Traits 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 Smile dimples No smile dimples

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 ______Date ______Lab. Take a Class Survey

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 ______Date______CER. Take a Class Survey

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.