Engineering Design Process Applied to Who Gets the Cabbage? …images.pcmac.org/Uploads/MCPSS/MobileCounty/Departments/... · 2019-09-25 · Prior to the day for this lesson, assign

Who Gets the Cabbage? Grade 7 math Q2 6.29.12

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Engineering Design Process Applied to

Who Gets the Cabbage? Designer Cabbage

Goal: Create a cabbage that is resistant to the Cabbage White Butterfly larva.

Problem: Use selective breeding to breed two parent crops that carry specific

traits for making cabbages more insect resistant.

Research: Gather information on cabbage traits

to change, selective breeding, and calculating

probability from dihybrid Punnett squares.

Develop: Discuss multiple solutions for creating

cabbages with insect-resistant traits.

Choose: Decide which traits you will crossbreed

to produce insect-resistant cabbage.

Create: Select cabbages to crossbreed based on phenotypes for traits you

selected. Use the genotypes of these cabbages to produce offspring.

Test and Evaluate: Determine the theoretical probability of breeding a cabbage

that contains the dominant trait selected.

Communicate: Present your findings and calculations in a method of your choice

to persuade a company to choose your solution.

Redesign: Choose the two best options for breeding to create a third generation

of cabbage and calculate the compound probability of the chosen traits occurring

in this generation.

Note: The Engineering Design Process (EDP) fits seamlessly with the 5-E model. For the purpose of focusing teachers and students on engineering, the EDP headings are used in this lesson.


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Engineering Design Challenge

Project Title: Who Gets the Cabbage? Designer Cabbage

Project Sources: MCPSS STEM Pilot Teachers

http://tinyurl.com/cx858ev

http://tinyurl.com/7czbaz2

http://tinyurl.com/26bcbk7

Project Submitter: STEM Improvement Lesson Development Team

Grade Level/Subject: Math, Grade 7, 2nd Quarter

Lesson Description: Through this hands-on experience, students will apply the Engineering Design

Process (EDP) to solve a problem. Teams will gather information about cabbage destruction by the larva

of the Cabbage White Butterfly. They will research information to determine genetic traits that might

produce a cabbage that is more resistant to the larvae of this butterfly. They will use selective breeding,

and their knowledge of how nature works to crossbreed cabbages and to help them select those most

likely to produce the desired solution. Teams will then use dihybrid Punnett squares evaluate their work.

Engineering Challenge: A biotechnology corporation has asked you to come up with a solution for a

serious problem. Larvae of an invasive species, the Cabbage White Butterfly, are destroying award-

winning cabbage in Elkmont, Alabama. As environmental scientists, you will decide what traits of the

cabbage to alter so that it is resistant to these larvae.The challenge is to selectively breed cabbages that

carry specific traits that would make them resistant to damage from the larvae.

Engineering Content Standard

2.2: Describe how engineering and science are different but mutually reinforcing endeavors.

Connection: Engineers often rely on the work of scientists to help them design solutions to

problems.

http://tinyurl.com/cx858ev

http://tinyurl.com/7czbaz2

http://tinyurl.com/26bcbk7


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MCPSS Mathematics to support the engineering challenge:

Understand that the probability of a chance event is a number between 0 and 1 that expresses the likelihood of the event occurring.

Develop a probability model and use it to find probabilities of events.

Compare probabilities from a model to observed frequencies. Find probabilities of compound events using organized lists, tables, tree diagrams, and simulation.

MCPSS Science to support the engineering challenge: 11.0. Identify Mendel’s laws of genetics

11.02. Use a monohybrid and dihybrid Punnett square to predict the probability of traits being passed

from parents to offspring.

Learning Objectives:

Students will . . .

Describe how engineering and science are different but mutually reinforcing endeavors.

Solve real-life and mathematical problems posed with compound probability using tools

strategically.

Describe the methods and role of technical communications for sharing results and conclusions.

Use knowledge of how nature works to genetically engineer a solution to a problem with an

invasive species.

Materials required:

For each class: Engineering Design Process Poster

PowerPoints titled: Who Gets the Cabbage?

Computer and Projector

For each team of 3-4 students:

Cabbage Cards – 1 set per team of 3-4

Crayons (2 Different Colors Per Team)

Trait Research Handout (1 per student)

Dihybrid Punnett Square handout (2 per team, or 1 for each pair of team members)

Index cards (1 per student)

Team Materials provided for each team by the teacher:

Materials for students to use in their presentations to Monsanto. These might include chart paper,


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scissors, tape, extra writing paper, stationary, etc.

Teacher Preparation: Day 1

Prior to the day for this lesson, assign students to teams of 3 or 4. They should be prepared to go

directly to their team areas when they arrive on Day 1.

Read the entire lesson carefully and be familiar with the handouts and materials. Study the page titled Teacher Preparation: Punnett Squares and Probability. This is for your

information if you need to review Punnett squares. Do not use it as a student handout. Set up AV equipment and prepare to show the Who Gets the Cabbage? slides.

Display the Engineering Design Process poster in a prominent place.

Prepare one set of Cabbage Cards for each team. Use this procedure:

o Copy each Cabbage Card with the pictures on the front and the genotypes on the back.

o Copy Cabbage Cards #1 and #2 on red paper.

o Copy Cabbage Cards #3 and #4 on green paper.

o Laminate the cards that represent the waxy trait (Card #1 and #3.)

o Cut the cards apart.

Copy the Trait Research Handout (1 per student)

Copy the Dihybrid Punnett Square handout (1 for each pair of team members)

Place an index card for each student in the team area.

Have a copy of the Letter to Students Agricultural Engineering Teams available

Teacher Preparation: Day 2

Display the Engineering Design Process poster in a prominent place.

Prepare to distribute the Dihybrid Punnett Square handouts to the students.

Set up AV equipment and have the PowerPoint ready to show.

Have the Letter from the biotechnology corporation available.

Provide one index card per student.

Provide materials students can use for their presentation.

Prerequisite knowledge:

Before this lesson: Students need to have experience with using and interpreting simple (monohybrid)

Punnett squares from their science work. From math they should know already know how to calculate


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simple probability, percentages, and ratios.

NOTE: If possible, the science engineering challenge, “What’s Bugging You?” should be completed before

this math challenge is introduced.


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Who Gets the Cabbage? Designer Cabbage

Grade 7 Math, Quarter 2

Day 1

Engineering Connection: Engineers and scientists work hand-in-hand to solve many types of

problems. This challenge represents an effort to control pests and parasites that infect and destroy

cabbage crops. Environmental engineers, agricultural engineers, and scientists are working

together to solve this problem, using selective breeding as one approach.

DEFINE THE PROBLEM (7 min)

Display Slide 1 as students arrive and move to their team areas.

Explain that students will be playing the role of student engineers for the next two

days. Tell them they will be working on an engineering challenge related to a science

engineering challenge they did (or will do). If students have already begun their science

engineering lesson, then ask students to explain what they are doing. (They are

developing a larva that will be unable to survive and destroy crops. This larva is from the

Cabbage White Butterfly.) Then explain that you have further news for them about the

Cabbage White Butterfly.

Indicate Define the Problem on the Engineering Design Process poster. Remind them

that engineering is about solving problems. They use math and science to help them

with this task. Science, math, and engineering all are connected. Each field depends on

the others and contributes to the others. Engineers often rely on the work of scientists

to help them design solutions to problems.

Help students understand the problem for this challenge. Read the Letter to Student

Agricultural Engineering Teams to the class. Ask if any students have a question about

the problem. (To use selective breeding to develop a cabbage that will be resistant to the

larva of the Cabbage White Butterfly.)

RESEARCH (5min)

Establish an understanding of the selective breeding process. Tell students that for

centuries, humans have tried to breed better crops. They do this by selective breeding -

carefully choosing parents plants that have the traits they want.


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Call attention to the fact that the Engineering Design Process always involves research –

gathering information they need to solve the problem. Science plays a big role in this

part of today’s engineering problem. We’ll be researching selective breeding.

Explain the steps in selective breeding. Tell teams that they may already know about

selective breeding from science. Show Slide#2 and explain that this is the process we

will use to develop the kind of cabbage Moorhouse Corporation has asked for – a

cabbage that is resistant to the larvae of the Cabbage White Butterfly.

Distribute materials. Give each student a copy of the Trait Research Handouts.

Give each team a copy of the Dihybrid Punnett Square handout.

Tell students that the Trait Research handout will help them with Step 1 on the slide:

Decide which traits are important. Each team member should begin by reading and

scoring the traits (yes, no, or maybe) according to whether he or she thinks it will make

the cabbage more resistant to the larva of the white cabbage butterfly.

DEVELOP and CHOOSE (15 min)

Guide team members to discuss their ideas about the different traits. They should

reach consensus on two traits that might allow the cabbage to be resistant to the larvae

of the Cabbage White Butterfly. After choosing the two traits they like best, team

members should work together in pairs to complete Part 1 of the Dihybrid Punnett

Square handout. Monitor teams as they discuss trait research handouts in teams and

complete Part 1 of the handout.

Quickly review Punnett squares with the students. They should already have some

experience with these from science. Show Slide #3 to remind them of these facts:

The letters represent alleles (uh leels) which make up the genes. Genes give the

cabbage its specific traits.

Capital letters represent dominant traits. If an offspring inherits even one of these

alleles it will display that trait.

Lowercase letters represent recessive traits. An offspring will not show a recessive

trait unless it inherits two recessive alleles, shown by two lowercase letters.

Show Slide #4. Direct students to copy the Punnett square on a 3X5 card and fill in the squares.

Review probability with the students. After students have completed their cards, show

slide #5, which shows the correctly filled in Punnett square and let students check their


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answers. Then ask the questions on the slide. (Answers: 1: two cabbages will be dark. 2:

two cabbages will be light. 3: P = 0.5, or 50% or ½. 4: P = 0.5, or 50% or ½.)

Lead team pairs to complete Part 2 of the Dihybrid Punnett Square handout. You should

be familiar with Part 2 in order to help them select the correct Cabbage Cards and answer

questions teams may have about the Punnett squares.

When teams complete Part 2, each team pair will select one of the offspring from the

parent cabbages they bred. They should select an offspring that they think might make

cabbage most resistant to the butterfly larvae.

CREATE (18 min)

Introduce dihybrid Punnett squares. Show Slide #6. Explain that the dihybrid Punnett

square is used to determine the probability of an offspring receiving two traits.

Give students this information about the dihybrid Punnett square on the slide:

o Previously we used a Punnett square to identify the possible offspring for one trait.

o We can identify all possible offspring of the parent cabbages for two traits by using a

dihybrid Punnett square.

o The top and side of each box on this dihybrid Punnett square contains traits for

venom or no venom (Vv) and for dark or light (Dd).

Ask students how they would fill in the boxes on this Punnett square. After they suggest

ideas, show Slide #7. Ask students what they notice about how the letters are arranged in

the squares. (The capital letter of each trait comes before the lower case letter of that same

trait.)

Note: You may want to show the Cabbage Cards to the class and describe the choices.

(Example: Laminated cards mean waxy.)

Note: If you are running short on time, you may begin Day 2 here.

Important!

Once students have discussed solutions, explain to students that all cabbages will

contain the venom trait. Now teams should list venom as one choice and narrow their

best choice to just one trait in addition to venom.


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Point to an empty square on the slide and ask students to write down the genotype for this

offspring on the notecard they used previously. Then write the correct answer on the board

(or have a student do so) and let students check to see if they understand. If they don’t

understand, explain how to arrive at that answer, and then repeat the process so that

students understand how to fill in the genotypes correctly.

Show Slide #8 and let students examine the completed dihybrid Punnett square. Ask if

students have any questions about the gene combinations.

Explain that team pairs will now identify all of the possible offspring of their parent

cabbages by looking at both traits – the venom trait and their team trait – at the same

time. Direct pairs to look at Part 3 in their handout. After they fill out answer #2, give them

the following information. Write these examples on the board as you explain to students how to

determine what letters (alleles) to put at the top of the square. Say:

You may have written something like this for your Cabbage 1 genotype: VvDd. (Write VvDd on the board.) Explain that to fill out the top part of the square pairs will need to cross each V or v with each D or d. Say: In other words, your Cabbage 1 genotypes would be VD, Vd, vD, and vd. (Write each genotype on the board as you name it.) Explain that those genotypes are what students will write at the top the four squares on their Punnett square. They will write the genotypes for Cabbage 2 down the side. Show Slide #6 again to help students visualize what they should do. Remind students that their team trait is not represented by a “D” or “d.” They should use the genotype they wrote for Cabbage 1, writing the letters (alleles) at the top of the Punnett square on the handout. Then they should repeat this for Cabbage 2, writing those letters down the side.

When they get to number 6 on their handouts, tell students:

Watch out! You may be looking for a recessive trait rather than a dominant trait! In other

words, your team trait may be represented by two lower case letters.

Tell students to complete the work on Part 3 of their handout.


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Walk around the room and monitor as students work in these sections. Be prepared to

help students

o Determine how to fill in the letters for the team trait they selected.

o Correctly fill in the squares in the dihybrid Punnett square

o Understand how to identify the offspring that inherited both traits.

Guide students to figure the probability of their parent cabbages producing offspring

which have inherited both of the traits they want. When students have identified the

number of offspring inheriting both traits, ask:

How many total combinations are in the Punnett square? (16)

How many total squares did you identify with your desired genotype?

Tell students that on Day 2 they will figure out the compound probability that their cabbage

parents will produce offspring with the desired traits and communicate this information to

Moorhouse Corporation.

Note: Teacher Questions

1. Which boxes represent the cabbage inheriting the venom trait? (All boxes that

contain capital ‘V’.) Students should shade these boxes with one color crayon.

2. Which boxes represent the cabbage inheriting the second trait? (This trait may be

represented by a capital letter or by two lowercase letters, depending on whether it is

dominant or recessive.) Students should shade these boxes with another color

crayon.

3. When students complete their shading, some boxes will contain both colors. These

boxes represent the offspring that inherited both traits.


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Day 2

EVALUATE (10 min)

Indicate the Engineering Design Process poster and ask students to mention one or two of

the stages and what they did for each stage. Explain that today teams need to evaluate the

effectiveness of their work and see if they have solved the problem posed by Moorhouse.

Ask a volunteer to tell what the problem was. If needed, read the last paragraph of the

letter from Moorhouse aloud.

Calculate the compound probability of the chosen parent cabbages producing offspring

with the desired traits.

Tell students they will now determine the probability that the cabbages they chose could

produce offspring with the two traits they think would help to make them resistant to the

Cabbage White Butterfly larva.

Show Slide #9 and say:

Let’s look at the Punnett square where we were trying to produce a dark colored cabbage

with venom. Dark color is dominant. How many squares with dark colored cabbages with

venom do you see? (The green colors show that there are 6 out of 16 or 3/8.)

Explain that 12 out of 16 or 3/4ths of the combinations had the trait for venom and 8 out of 16 or ½

had the trait for dark color.

Show Slide #10. Be sure students understand how to calculate compound probability and

what this means. They should be able to explain that a probability of .375 is less than 50 %.

Ask:

Do you think these two parent cabbages are likely to produce a venomous, dark cabbage?

Explain to students that when they did the single Punnett square the probability of getting a dark cabbage was ½ and the probability of getting a venomous cabbage was ¾. Have students multiply those two probabilities together (1/2 times ¾ equals 3/8). Point out that one way to find the probability of an organism inheriting two traits that are not dependent on each other scientists is to use a dihybrid Punnett square. We call events such as these, that are not

Teacher note: The compound probability will be the number of squares with the desired

genotypes divided by the total number of squares.


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dependent on each other, independent events. Another way to find the probability of two independent events is to find the simple probability of each event and multiply. [If A and B are independent events, then P(A, then B) = P(A) X P(B)]

COMMUNICATE (30 min)

Allow teams to decide how to present their findings to Moorhouse Corporation. Suggest

that student pairs come up with a creative way to organize and display their findings and

calculations in a manner that would encourage the company to use their chosen cabbages

for establishing a selective breeding system.

Some communications options they might consider include:

Pamphlets

Powerpoint Presentations

Posters

SMARTBoard Notebooks

Other ideas they wish to use for which you have materials

CONCLUDE: (5 min)

Ask students to prepare an exit slip. Ask each one to write on an index card the most

important or interesting thing he or she learned during this lesson. Collect the Dihybrid

Punnett Square handouts so that you can review the teams’ work.

Documents

Engineering Design Process Applied to Who Gets the Cabbage? …images.pcmac.org/Uploads/MCPSS/MobileCounty/Departments/... · 2019-09-25 · Prior to the day for this lesson, assign