Cross-Curricular Project Unit 5

It's All in the Genes

Introduction
Mirror, mirror on the wall... why do I look like my parents at all? You've been selected to join a team of genetic researchers to find an answer to this very question. On this adventure, you'll research basic genetic lingo and learn how to use a Punnett square. Then you'll gather information about the genetic traits of your classmates. You'll also make genetic predictions based on an analysis of your findings. So grab your lab coat and your probability and statistics tool kits. This is one adventure you don't want to miss.

The Task
Below is a brief description of each challenge you will complete. The Process section has a detailed description of each activity. Also, the Guidance section has some helpful hints, and the Resources section has some useful Web sites that you are encouraged to use.

Gene Challenge 1
First, use the Internet to research the Punnett Square and its role in genetics. Then you will do a few practice problems using a Punnett Square.

Gene Challenge 2
Next, collect and record some specific genetics-related information about the students in your class.

Gene Challenge 3
Finally, analyze and calculate different statistics based on your data. Then, analyze a given couple and answer questions about their potential offspring.

The Process
Below is a detailed description of each challenge.

Gene Challenge 1

Using the Internet, find the definition of the following words: alleles, dominant, genotype, heterozygous, homozygous, phenotype, Punnett Square, and recessive.
Locate and read different descriptions of the Punnett Square on the Internet. Then, locate four different problems on the Internet that are solved using a Punnett Square. Print these four problems, and then solve each problem.
Then write a 1-2 paragraph response to the following questions:
- What is the Punnett Square?
- How is the Punnett Square used in genetics?
- How is math involved with the Punnett Square?

Gene Challenge 2

Now it is time for you to collect some data. Listed below are eight different pairs of traits. One trait will be labeled D for dominant, and one will be labeled R for recessive. It is your job to consult with each person in your class and find out which traits they have. Once you have tallied up the different traits, create a table that displays all of your collected data.

Trait	Symbol	Dominant or Recessive
Non-blue eyes -or- Blue eyes	B b	Dominant Recessive
Unattached Ear Lobes -or- Attached Ear Lobes	E e	Dominant Recessive
Widow’s Peak -or- Straight Hairline	W w	Dominant Recessive
Dimples (2 dimples or 1 dimple) -or- No Dimples	D d	Dominant Recessive
Bent Back Thumb -or- Straight Thumb	T t	Dominant Recessive
Dark Hair -or- Light Hair	H h	Dominant Recessive
Can Roll Tongue -or- Cannot Roll Tongue	R r	Dominant Recessive
Bent Pinky -or- Straight Pinky	P p	Dominant Recessive

After you have collected all the data and created a table, create a graph that represents all of your collected data. Remember, you can choose from the following graphs:
- bar graph,
- circle graph,
- line graph, or
- line plot.

Be sure to label your graph properly.

Gene Challenge 3
Now it is time to analyze the data you have collected. Using your knowledge of Punnett Squares, you will make some predictions based on your calculations.

Print and then complete Worksheet 1.

Worksheet 1

NAME:__________________________________

DATE:___________

Use the data you have collected to answer the following questions.

1.	Create a tree diagram that illustrates the number of possible combinations of the following traits: non-blue/blue eyes, can roll tongue/cannot roll tongue, and dark hair/light hair. Using the Fundamental Counting Principle, how many different combinations should you come up with?

2.	What is the probability that one of your peers would have all of the following characteristics: dimples, bent pinky, and attached ear lobes? What is the probability of each characteristic separately? For example, what is the probability of one of your peers having dimples? Assume that it is equally likely to have each trait.

3.	What is the probability that someone in your classroom will have all of the dominant traits? All of the recessive traits?

4.	If you were to use the data you collected from your classmates as a sample, what percent of your school would have no dimples? Bent thumb? Widow’s peak?

5.	Now that you have answered a few questions, find the total number of students in your grade. Set up a ratio, and predict the number of people that will have the following characteristics.

	Blue eyes:
	Unattached ear lobes:
	Straight hair line:
	Dimples:
	Straight thumb:
	Light hair:

To answer the following questions, work with a partner. Using the individual data about yourself, determine the probability of a child resulting from a cross of your genetic traits having each particular characteristic.

6.	Set up a Punnett Square, and fill it in for eye color. What is the probability that a child resulting from a cross of your genetic traits would have blue eyes?

7.	Set up a Punnett Square, and fill it in for hair color. What is the probability that a child resulting from a cross of your genetic traits would have dark hair?

8.	Set up a Punnett Square for the ability to roll your tongue. What is the probability that a child resulting from a cross of your genetic traits could not roll their tongue?

9.	Set up a Punnett Square for bent/straight pinky and widow’s peak/straight hairline. What is the probability that a child resulting from a cross of your genetic traits would have a straight pinky and a widow’s peak?

10.	Set up a Punnett Square for unattached/attached ear lobes and bent back thumb/straight thumb. What is the probability that a child resulting from a cross of your genetic traits would have unattached ear lobes and a bent back thumb?

Once you have analyzed your data, print and then complete Worksheet 2.

Worksheet 2

NAME:____________________________________

Date:___________

Listed below is a description of the Gene Family. Use this data to answer the following questions.

Family Member	Genotype	Phenotype
Grandma Gene	Bb ee WW Dd TT hh rr PP
Grandpa Gene	Bb EE Ww Dd tt Hh Rr pp
Grandma DNA	bb ee Ww DD tt HH Rr Pp
Grandpa DNA	Bb ee ww dd Tt Hh Rr PP

1.	Using your knowledge of Punnett Squares, fill in the Phenotype section of the table above.
2.	Mother Gene is the daughter of Grandma and Grandpa DNA. What is the probability that Mother Gene will have brown hair and a bent thumb?
3.	Again, what is the probability that Mother Gene will have a bent pinky, non-blue eyes, and a straight hairline?
4.	Now, Father Gene is the son of Grandma and Grandpa Gene. What is the probability that Father Gene will have unattached ear lobes and cannot roll his tongue?
5.	What is the probability that Father Gene will have all recessive traits?
6.	Mother Gene and Father Gene decided to have a child. Daughter Gene is their first child. What is the probability that Daughter Gene will have blue eyes?
7.	Mother Gene and Father Gene decided to have another child. Son Gene is their second child. What is the probability that Son Gene will have dark hair and dimples?
8.	What is the probability that both Son Gene and Daughter Gene will have attached ear lobes and a straight hairline?

Guidance
If you are having difficulties with a particular challenge, take a look at some of the helpful hints below.

Gene Challenge 1

When finding definitions on the Internet, make sure that you cite your sources.
When writing your 1-2 paragraph response, be certain to explain the connection between math and the Punnett Square.

Gene Challenge 2

When creating a table, make certain that you include each trait and the total number of people in your class that have each trait. Therefore, your table could only have 2 columns.
When creating a graph take into account the type of data you are working with. Are you working with one source or with more than one source? To review graphing data, refer to Lessons 11-1 through 11-3 and 11-8 in your text.

Gene Challenge 3

Worksheet 1
- To review ratios, refer to Lesson 4-1 in your text.
- When completing Questions 6-10 on this worksheet, if you have the dominant trait, you can either figure out what your genotype is using your parent’s phenotype information or you can make an educated guess. If you have the recessive trait, then you should know what your genotype is.
Worksheet 2
- For Questions 2-5, it would be beneficial for you to set up a Punnett Square to see the different possibilities!
- For Questions 6-8, it would also be beneficial for you to set up a Punnett Square for both the parents individually and then another Punnett Square using the information from the individual Punnett Squares. You might have to make more than one Punnet Square or you can use your knowledge of combinations to calculate the probabilities!
Here are some different Lessons in your text that will help you complete Worksheets 1 and 2: Lessons 12-1, 12-2, and 12-3. Prerequisite skills, p.673 may also be helpful.

Resources
Listed below, you can find some helpful Web sites. Remember, you are not limited to these Web sites.
Baby Steps through the Punnet Square
Chromosome Kindergarten
Google
Human Genetics
Mendel’s Genetic Laws
Yahooligans

Conclusion
Great work! Your probability and statistics tool kits likely came in very handy on this quest. Did you find out some interesting things about your classmates? You probably found out some interesting things about your own genetic traits. We hope you enjoyed your journey through the fascinating world of genetics and now see how large a role mathematics plays in understanding this world.