UKanTeach 5E Lesson Plan

Author (s): Cody Alley & Jake SkinnerTeam Members: Cody Alley & Jake Skinner

Title of Lesson: Hardy-Weinberg Lab

Lesson #: 2Date lesson will be taught: Wednesday 4/17/2013Grade level: 9th

Lesson Source (kit, lesson): The lab portion of this lesson was provided by Beth Esco

Concepts/Main Idea – in paragraph form give a broad, global statement about the concepts and vocabulary you want students to understand as a result of doing this activity (see Model lesson example):

The overall goal of this lab is to familiarize the students to the Hardy-Weinberg equation and how it relates to allelic frequencies in populations. By the end of this lesson students should be able to understand how population size, rates of mutations, initial frequencies of alleles, dominance etc. effect evolutionary change in populations of generations.

Objective/s- Write objectives in SWBAT form…The Students Will Be Able To:

EvaluationIn the space below, explain the type(s) of evaluation that will provide evidence that students have learned the objectives of the lesson (formative and summative). You will provide student copies at the end of the lesson.

- Collect allele frequencies from a simulation.- Predict allele frequencies under Hardy-Weinberg equilibrium for

future generations.- Calculate actual allele frequencies- Compare expected allele frequencies to actual allele

frequencies.- Modify the allele frequencies based on pressures of natural

selection- Decide if a population is in Hardy-Weinberg equilibrium or not.

- Evaluation will be carried out in both a summative and formative manner. Throughout the assignment students will be asked questions by the teacher in order to gain some formative assessment. More formative assessment will gathered during class discussion and when the teacher is monitoring the groups and answering questions. The summative evaluation of this exercise will be conducted during and after the exercise. During the exercise students will be calculating mathematical formulas and illustrating their results in a graph. After the exercise there will be a quick quiz that sums up what the students went over during the day.

Kansas Science and Math Standards- Include standard, benchmark and indicator where applicable

Science: (standard, benchmark, indicator)

STANDARD 1: SCIENCE AS INQUIRY

Grades 8-12 SCIENCE AS INQUIRY – The student will develop the abilities necessary to do scientific inquiry and develop an understanding of scientific inquiry.

Benchmark 1: The student will demonstrate the abilities necessary to do scientific inquiry.

Indicators: The student…

2. ▲ actively engages in investigations, including developing questions, gathering and analyzing data, and designing and conducting research

b. identify and test variables (independent, dependent, and variables to be kept constant).

c. using methods for gathering data that is observable, measurable, and replicable.

STANDARD 3: LIFE SCIENCE Grades 8-12

LIFE SCIENCE – The student will develop an understanding of the cell, molecular basis of heredity, biological evolution, interdependence of organisms, matter, energy, and organization in living systems, and the behavior of organisms.

Benchmark 2: The student will demonstrate an understanding of chromosomes, genes, and the molecular basis of heredity

Indicators: The student…

4. understands gametes carry the genetic information to the next generation.

- c. Alleles, which are different forms of a gene, may be dominant, recessive, or co-dominant.

Benchmark 3: The student will understand biological evolution

Indicators: The student...

1 ▲understands biological evolution, descent with modification, is a scientific explanation for the history of the diversification of organisms from common ancestors.

- d. The frequency of heritable traits may change over a period of generations within a population of organisms, usually when resource availability and environmental conditions change as a consequence of extinctions, geologic events, and/or changes in climate.

2. understands populations of organisms adapt to environmental challenges and changes as a result of natural selection, genetic drift, and various mechanisms of genetic change.

- b. Natural selection and genetic drift occur within populations or organisms.

5. understands the primary mechanism acting on variation is natural selection.

- a. Favorable heritable traits are more advantageous to reproduction and/or survival than others.

- c. Individuals with beneficial traits generally survive to reproduce in greater numbers.

- d. Favorable heritable traits tend to increase in the population through time if the selective pressure is maintained.

6. understands biological evolution is used as a broad, unifying theoretical framework for biology.

- d. Natural selection, genetic drift, genomes, and the mechanisms of genetic change provide a context in which to ask research questions and help explain observed changes in populations.

Math: Must include Common Core Math Practice Standard and tested indicator (2003 standards), if applicable.

Materials list (BE SPECIFIC about quantities) for Whole Class:

- Powerpoint with instructions and bell ringer

per Group:

- Cup with 60 blue beads and 40 green beads

- 1 Hardy-Weinberg Lab Packets

- Pencil

- Calculator if necessary

per Student:

Advance preparation:

- Print 12 Hardy-Weinberg Lab Packets- Have 12 cups with beads counted- Create groups of 3 or 4 before hand

Include handouts at the end of this lesson plan document (blank page provided)

Accommodations: Include a general statement and any specific student needs

- Be ready to help create a more visual experience for ELL students.

- Students how are hearing or visually impaired may need the help of a paraprofessional

- If needed project directions on board with larger print for those who cannot see very well

Safety: Include a general statement and any specific safety concerns

- Make sure that all backpacks are put away in order to prevent students from falling.

- Strive to create an equal learning environment for students who may be shy, ELL, or subject to bullying, etc.

- Make sure students understand it is okay to be wrong in order to create a learning environment that feels safe.

Engagement: Estimated Time: 10 min

What the teacher does AND how will the teacher direct students: (Directions)

Probing Questions: Critical questions that will connect prior knowledge and create a “Need to know”

Expected Student Responses AND Misconceptions - think like a student to consider student responses INCLUDING misconceptions:

Begin by asking students questions about the Hardy-Weinberg Law. Make sure to write the equation on the board.

Ask some questions about the equation itself.

If students are having a hard time coming up with answers as to why we make the equation equal to zero draw a pie chart on the board and get them to understand that the entire pie chart is the entire population of the organisms.

Explain to the class that we will be exploring the Hardy-Weinberg Law and how it allows biologists to test whether a population is experiencing one of the factors that can affect genotype frequencies. Ask them if they can remember what the five requirements of Hardy-Weinberg equilibrium are.

Let the class know that they will be exploring the effects of natural selection on a population that appears to be in Hardy-Weinberg Equilibrium.

Who can explain what the Hardy-Weinberg Law is? What does it represent?

What about the organisms is not changing?

So what does each of these variables represent?

Why do you guys think we make the equation equal one? What does this allow us to do?

So what are the five requirements for a population to be in Hardy-Weinberg equilibrium?

It is when a population of organisms is not changing over generations…

The frequency of alleles…

P2 = The frequency of AA individuals, 2pq = The frequency of Aa individuals, and q2 = The frequency of aa individuals…

Since we are talking about a population we can treat them as percentages of the whole population…

No mutations, very large population size, no migration, random mating, and no natural selection…

Teacher Decision Check Point: how do you know your students are ready to move forward?Once the class has showed a general understanding of the principles of the Hardy-Weinberg law and have answered majority of the questions asked.

Exploration: Estimated Time: Max of 50 min

What the teacher does AND what the teacher will direct students to do: (Directions)

Probing Questions: Critical questions that will guide students to a “Common set of Experiences”

Expected Student Responses AND Misconceptions - think like a student to consider student responses INCLUDING misconceptions:

Once students are in their groups begin by having one person from each group come and get a cup of beads and a lab kit.

After students have set down with their materials have them read the objective and introduction to the lab. Make sure that students bring their focus back to you when they are ready to read the procedure. This can be achieved by having them raise their hands when they are finished.

Read the first paragraph of the procedure to the class. See if anyone can answer what the beginning frequencies are for the alleles.

Read part 1 to the class. Ask them why it is necessary for them to shake the cup and not look while picking out the beads.

Have the students read and complete steps 2 and 3. Make sure to let them know that it is okay to be confused and ask questions if they need to. Once they have completed filling out table 2, ask them some questions about the observed vs. expected genotype frequencies.

Once they have completed step 4 of part 1 and all of the class has reported their results give them the class results. Ask them why they think the observed class results are even closer than the individual group results.

So what will be the initial frequencies of each allele?

Why is it important that we shake the beads and avoid looking at them while picking pairs from the cup? Which of the five HW requirements would we possibly be violating?

Are the expected and observed frequencies different? Do you think that they are significantly different?

Compare your group’s results to the class results. Which one has observed frequencies that are more similar to the expected frequencies? Why do you think that is the

A will be 0.6 and a will be 0.4….

We need to make sure that we are randomly choosing the beads in order to ensure that random “mating” is occurring…

They are kind of different… I don’t know…

The class results are more similar… This is because of the fact that the population size is larger…

Students may need some help getting started during part 2. Explain that table 4 is for their group’s results and that table 5 is for the class’s results. These two different tables allow the class to compare and contrast.

Have the students try to get through steps 2-4 on their own. If they need help or seem like they are getting off task some assistance should be provided. The key here is to try and pace the students so that everyone is ready to exchange results with another group around the same time.

Step 6 of part 2 may also give the class a difficult time. Once the students have completed this step of the lab they should be able to get to graphing portion on their own.

Make sure that students understand that the graph portion of this lab is intended for them to see the differences in allele frequencies with and without natural selection’s influence. If time is starting to become a constraint make sure that the students finish in order for the class to come together and go over the lab before they move on to the worksheet.

case?

Teacher Decision Check Point: how do you know your students are ready to move forward?Once all of the students have finished their graphs and are ready to discuss the results…

Explanation: Estimated Time: 10 min

What the teacher does AND what the teacher will direct students to do: (Directions)

Clarifying Questions: Critical questions that will help students “Clarify their Understanding” and introduce information related to the lesson concepts & vocabulary – check for understanding (formative assessment)

Expected Student Responses AND Misconceptions - think like a student to consider student responses INCLUDING misconceptions:

Begin this part of the lesson by asking the class some questions about the graph. Bring up the idea of why there is a greater change at the onset of natural selection.

So what are we seeing here on the class results graph?

How does it compare to your group’s graph?

Does the recessive allele disappear immediately? Why do you think that is the case?

Why do we not see a constant rate of change in the graph after natural selection was introduced?

In the beginning this population is experiencing H-W equilibrium and then when it changes it is being influenced by natural selection…

It is pretty similar even though at the end of it actually goes up again…

No… Because it is “hidden” in the heterozygotes… Because we are only eliminating half of the individuals…

I don’t know… Because there are a smaller number of individuals with aa genotype each time…

Teacher Decision Check Point: how do you know your students are ready to move forward?

Elaboration: Estimated Time: 10 min

What the teacher does AND what the teacher will direct students to do: (Directions)

Probing Questions: Critical questions that will help students “Extend or Apply” their newly acquired concepts/skills in new situations

Expected Student Responses AND Misconceptions - think like a student to consider student responses INCLUDING misconceptions:

Bring up the possibilities of it being more advantageous of being a heterozygote. The example of sickle cell anemia could be brought up here. This example is optional if time permits.

If time is an issue than go straight to the question about whether or not heterozygous advantage would ever lead to a disappearance of homozygous individuals.

Let’s say that there is a situation where it is more advantageous to be a heterozygote. I am sure that all of you have heard of sickle cell anemia. This disease affects the shape of the hemoglobin of red blood cells. In this situation there are two alleles; one that is for normal shaped hemoglobin (A) and one that is for sickle shaped hemoglobin (S). When malaria infects a human part of its life-cycle requires being inside red blood cells. The sickle cell phenotype adds some protection to the malaria parasite and thus adds to the fitness of that individual. However if that person is homozygous for the S allele they experience many health problems and a premature death. This is a great example of when it is advantageous to be heterozygous. Those with AS genotypes are protected to a degree from malaria and do not experience the same complications as SS individuals. What do you think our graph would look like if it were the heterozygotes that were selected for?

Would we ever see the homozygous genotypes completely disappear?

We would see that Aa would increase while AA and aa would decrease….

No since Aa and Aa crossing would always have a 25% chance of having progeny with AA and aa… Therefore we would see a 50/50 chance of seeing a homozygote for either AA or aa.

Evaluation: Estimated Time: 10 minCritical questions that ask students to demonstrate their understanding of the lesson’s performance objectives.Formative Assessment(s): In addition to the final assessment (bell ringer or exit slips), how will you determine students’ learning within this lesson: (observations, student responses/elaborations, white boards, student questions, etc. Look at your Teacher Decision Check Point)?

This will be done throughout the lab based on how the students are responding to the questions.

Summative Assessment: Last 2 pages on lab, embedded below.

Embedded Documents: