Cells, Genetics and Biotechnology - Toshiba · Cells, Genetics and Biotechnology ... • Plastic...

Cells, Genetics and

Biotechnology

• Cell Factories

• Cell Dissection

• Pipe cleaner Mitosis

• Marshmallow Meiosis

• Transcription and Translation

• Animal Genetics

• Fruit Fly Ranching

• DNA Extraction

• Gel Electrophoresis

Rural Science Education Program A partnership between Oregon State University

and rural K-12 schools

Designers, editors, and contributors

Sujaya Rao, editor and director, Rural Science Education Program (Associate Professor of Entomology) Joy Waite, author (Graduate Fellow, Rural Science Education Program) Sarah Gehlhar, author, (Graduate Fellow, Rural Science Education Program) Anne Halgren, author, (Graduate Fellow, Rural Science Education Program) Eryn Cramer, author, (Undergraduate Fellow, Rural Science Education Program) Denise Baumann, author, (Undergraduate Fellow, Rural Science Education Program) Jeff McGarvey, author (Science Teacher, Alsea School, Oregon) Sylvia Harvey, author (Science Teacher, Seven Oak Middle School, Oregon) Kathy Brandis, author (Science Teacher, Seven Oak Middle School, Oregon) Rural Science Education Program The Rural Science Education Program is a partnership between Oregon State University and local rural K-12 schools for enrichment of the science curriculum with hands-on science activities that encourage critical thinking in K-12 students about the impacts of agriculture on the environment and the implications of advanced scientific research on human lives. For More Information For more information about the Rural Science Education Program, contact Sujaya Rao (phone: (541) 737-9038; e-mail: [email protected]; fax: (541) 737-5725.

This material is based upon work supported by the National Science Foundation and Toshiba America Foundation. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and the editor, and do not necessarily reflect the views of the National Science Foundation or Toshiba America Foundation.

mailto:[email protected]

Lesson 1

Cell Factories

Objective: Students will understand how the organelles work together within a cell. Students will design a factory that is analogous to a cell and its organelles. Grade Level- 8-12 National Standards:

• Students should develop an understanding of structure and function in living systems • Students should develop understanding of the cell

Background Knowledge: Students should have a basic understanding of cell organelles. Materials:

• craft supplies • cardboard • construction paper • glue • reference materials on cell organelles

Procedure:

1. Students work in groups of four. 2. Each group chooses a product that could be produced in a factory (it can be real or

imaginary) 3. Using the reference materials as guides, groups create a model of the factory that

makes their product. They must assign each aspect of the factory process to an organelle.

4. Once the factory is completed each group must write an explanation of how the various factory parts are analogous to the organelles the group chooses.

5. Each group presents their factory to the class. 6. Each student completes their own assessment form about the project.

CELL FACTORY ASSESSMENT FORM – Please fill out a form for yourself.

Evaluation of:

1. Project exhibits understanding of cell structure and function.

1 2 3 4 5 very little Somewhat adequately accomplished distinguished

2. Project implies importance of the cellular organelles.


3. Project displays appropriate analogies.

1 2 3 4 5 very little Somewhat Adequately accomplished distinguished

4. Cell factory is efficient.


5. Group was well prepared for their presentation.


6. The project was original and creative.

1 2 3 4 5 Very little Somewhat adequately accomplished distinguished

7. The presentation kept my attention.


8. Overall quality of project.

1 2 3 4 5 Very little Somewhat adequately accomplished distinguished

Comments: ________________________________________________________

__________________________________________________________________

__________________________________________________________________

EFFORT: __Excellent __Very Good __Fair __I/group/individual could have done better

ASSESSMENT POINTS Points Possible Self Instructor 1. subject researched (10) ____ ____ 2. project completed on time (10) ____ ____ 3. worked as a group (10) ____ ____ 4. creation of a useful learning tool (10) ____ ____ 5. worked as an individual (10) ____ ____

Likes / Dislikes of Project:

__________________________________________________________________

__________________________________________________________________

Suggestions to improve:

__________________________________________________________________

__________________________________________________________________

Reference Material on Cellular Organelles Membrane - The major barrier of the cell, separating the inside of the cell from the

outside. It is this structure that allows cells to selectively interact with their environment.

Cytoplasm – A material that lies within the cytoplasmic membrane and holds everything

in a cell outside of the nucleus. Cytoplasm contains a lot of water and the other

organelles of the cell. It is made up of proteins, vitamins, ions, nucleic acids, amino acids,

sugars, carbohydrates and fatty acids. All of the functions for cell expansion, growth and

replication are carried out in the cytoplasm of a cell.

Cell wall – A rigid supporting wall located exterior to the plasma membrane in plants

and bacteria

Mitochondria – Spherical or elongated intracellular organelles that contain the electron

transport system and enzymes. They are often referred to as the “powerhouse” of the cell

and contain the molecular machinery for the conversion of sugar to energy.

Chloroplast – chlorophyll bearing intra-cellular organelle of plant cells. Chloroplasts are

the site of photosynthesis.

Vacuole – A membrane bound sac found within the cytoplasm. It functions in storage,

digestion, transport, and water elimination. Plant cells contain a very large vacuole that

plays an important role in maintaining turgor pressure.

Nucleus – The spherical cellular organelle that contains DNA and serves as the control

center of the cell

Endoplasmic reticulum (ER) – A 3-dimensional maze of connecting and branching

channels made by a continuous membrane. The ER is responsible for segregation of

proteins destined for export from the cell or for intracellular use as well as, steroid

synthesis, metabolism and detoxification of substances in the liver just to name a few

functions.

Golgi apparatus – Organelle composed of stacks of flattened membranous sacs. The

Golgi is mainly responsible for modifying, packaging, and sorting proteins.

Lysosome – Small round structure involved in the digestive activities of the cell in order

to break down food items for use by the mitochondria for energy.

DNA – Deoxyribonucleic acid (DNA) is present in a cells chromosomes and contains the

genetic information for the living organism.

Ribosome - Ribosomes are responsible for assembling the proteins of the cell. Ribosomal

subunits are synthesized by the nucleolus. They generally exist in the cytoplasm and

bound to the ER.

Plant CellPlant CellPlant CellPlant Cell

Animal CellAnimal CellAnimal CellAnimal CellAnimal CellAnimal Cell

Types of CellsTypes of Cells

Source : http://www.physicalgeography.net/fundamentals/6a.html

http://www.physicalgeography.net/fundamentals/6a.html

Lesson 2

Cell Dissection

Adapted from: http://www.askeric.org/Virtual/Lessons/Science/Biology/BIO0035.html

Objective: Students will recognize differences between prokaryote, plant, and animal cells. Students will be able to create a data table to explain the differences. National Standards:

• Students should develop an understanding of structure and function in living systems • Students should develop understanding of the cell

Background Knowledge: Students must be introduced to the concept that plants, animals, and prokaryotes are all made of cells. The three cell types have different structures, components, and functions making each cell type unique. The different organelles should be introduced and their different functions explained. Materials Needed:

• 4 colors of Jell-O – 1 box/cell • Various candies or objects to represent cellular organelles – see below under Plant and

Animal Cell • Plastic bags with twist ties • Plastic plates • Plastic knives • Plastic spoons • Gloves • Graph Paper

Procedure: A. Ahead of time (Another class could do the preparation)

a. Prepare cells as described below. b. Mix Jell-O as directed for “Jigglers” on box c. Fill plastic baggies with Jell-O, leaving only enough room to close bag. Allow Jell-o to start

to set, but do not allow to completely set. d. Insert “organelles” (example: ribosome = beads, mitochondria = mandarin oranges, etc.) e. Place plant and prokaryotic cells in small loaf pans to create a standard shape and allow

animal cells to free form. f. Close “cells” and allow to set in refrigerator several hours or overnight

NSF GK-12 Rural Science Education Program, Oregon State University http://cropandsoil.oregonstate.edu/gk12

Plant Cell Organelle Ingredient Membrane Plastic baggie Cytoplasm Jell-O (color #1) Cell Wall Jell-O (color #4 in another bag around 1st Jell-O

bag)* Mitochondria Mandarin Orange Segments Chloroplast Green jellybeans Vacuole Giant jawbreaker Nucleus Gumball Endoplasmic Reticulum

Ramen Noodles (dry)

Golgi Apparatus Licorice Ribbon

B. Class a. Handout instructions and assignment for lab and explain the process of dissection

and the safety issues involved b. Divide students into groups of two

• assign one partner as the dissector • assign the other as a recorder

c. Distribute a plastic knife, spoon, and plate to each group d. Distribute a “Jell-O cell” to each pair e. Allow students to dissect the cells and remind them to keep careful record of

everything they find (repeat for as many cell types as you want each group to dissect)

f. Clean up the cells and their organelles g. Get pairs back together and allow them to work on organizing their observations

into a data chart. (i.e. What did they find?, How many were in the cell?, What could the ingredient have represented?, etc.)

h. With their data chart complete and comparing to the diagrams given, can the students make an inference as to what kind of cell they dissected (plant, animal, prokaryote)?

i. Have the students hand in an organized data chart and a paragraph about their inferences as a lab write-up.

Animal Cell Organelle Ingredient Membrane Plastic baggie Cytoplasm Jell-O (color #2) Mitochondria Mandarin Orange Segments Nucleus Gumball Endoplasmic Reticulum Ramen Noodles (dry) Golgi Apparatus Licorice Ribbon Secretory Vesicles Mini Chewy Sweetarts

Lesson 3

Pipe cleaner Mitosis

Objective: To understand mitosis by making a model out of pipe-cleaners National Standards:

• Students should develop an understanding of reproduction and heredity • Students should develop understanding of molecular basis of heredity

Background Knowledge: Students should have a basic understanding of cell organelles. Materials:

• Pipe cleaners of various colors • String • Reference materials – Stages of Cell Cycle, Chromosomes, Stages of Mitosis

Procedure: Step 1- Take 2 pipe-cleaners of several colors each (=Chromosomes) and two pieces of string (=cell membrane) Step 2- Drop one set of the pipe-cleaners in a pile and place the string to form a circle around the pile then add the other set to duplicate the chromosomes-this is INTERPHASE Step 3- Pair up the colors- these are your sister chromatids in PROPHASE Step 4- Twist pipe-cleaners together in pairs- these represent your chromosomes at PROMETAPHASE Step 5- Line up the twisted pipe-cleaners along the centerline-this is METAPHASE Step 6- Untwist the pipe-cleaners and pull one of each color to opposite ends of your cell-this in ANAPHASE Step 7- Bring the end of the string together to form two circles touching each other and placing one set of each color pipe-cleaner in each-this is TELOPHASE Step 8- Separate the circles with the pipe-cleaners-this is CYTOKINESIS the final step to make two identical cells!

Reference material

Stages of the cell cycle

http://bhs.smuhsd.org/bhsnew/academicprog/science/vaughn/Student%20Projects/Paul%20&%20Marcus/Cell_Replication.html

From: http://www.rpgroup.caltech.edu/courses/aph162/2006/webpages/Projects/Alex-JinHong-Eileen/index.html Interphase

The cell is engaged in metabolic activity and preparing for mitosis (the next four phases that lead up to and include nuclear division). Chromosomes are not clearly discerned in the nucleus, although a dark spot called the nucleolus may be visible. The cell may contain a pair of centrioles (or microtubule organizing centers in plants) both of which are organizational sites for microtubules. 90% of Mitosis occurs in this stage.

Prophase

Chromatin in the nucleus begins to condense and becomes visible in the light microscope as chromosomes. The nucleolus disappears. Centrioles begin moving to opposite ends of the cell and fibers extend from the centromeres. Some fibers cross the cell to form the mitotic spindle.

Prometaphase

The nuclear membrane dissolves, marking the beginning of prometaphase. Proteins attach to the centromeres creating the kinetochores. Microtubules attach at the kinetochores and the chromosomes begin moving.

Metaphase

Spindle fibers align the chromosomes along the middle of the cell nucleus. This line is referred to as the metaphase plate. This organization helps to ensure that in the next phase, when the chromosomes are separated, each new nucleus will receive one copy of each chromosome.

Anaphase

The paired chromosomes separate at the kinetochores and move to opposite sides of the cell. Motion results from a combination of kinetochore movement along the spindle microtubules and through the physical interaction of polar microtubules.

http://www.rpgroup.caltech.edu/courses/aph162/2006/webpages/Projects/Alex-JinHong-Eileen/index.html

http://www.rpgroup.caltech.edu/courses/aph162/2006/webpages/Projects/Alex-JinHong-Eileen/index.html

Telophase

Chromatids arrive at opposite poles of cell, and new membranes form around the daughter nuclei. The chromosomes disperse and are no longer visible under the light microscope. The spindle fibers disperse, and cytokinesis or the partitioning of the cell may also begin during this stage.

Cytokinesis

In animal cells, cytokinesis results when a fiber ring composed of a protein called actin around the center of the cell contracts pinching the cell into two daughter cells, each with one nucleus. In plant cells, the rigid wall requires that a cell plate be synthesized between the two daughter cells.

Reference material Chromosomes

http://www.micro.utexas.edu/courses/levin/bio304/genetics/genetics.html

Chromosome: The self replicating genetic structures of cells containing the cellular DNA that carries its nucleotide sequence (linear array of genes). Homologous chromosomes: Chromosomes that match in size and shape. A pair of genes containing the same linear gene sequence, each derived from one parent. Sister chromatids: Chromatids derived from the same chromosome that still share the same centromere. Centromere: Area in a chromosome where spindle fibers are attached to move the chromosome during cell division. This is usually a constricted area of the chromosome called the “primary constriction.” Mitosis: The process of nuclear division in cells that produces daughter cells that are genetically identical to each other and to the parent cell. Meiosis: A two stage type of cell division in sexually reproducing organisms that results in gametes with half the chromosome number in the original cell.

http://www.cbs.dtu.dk/staff/dave/roanoke/genetics980218.html

http://www.cbs.dtu.dk/staff/dave/roanoke/genetics980218.html

Stages of Mitosis http://www.bbc.co.uk/schools/gcsebitesize/biology/cellprocesses/celldivisionrev2.shtml

Lesson 4

Marshmallow Meiosis

Based on http://www.iloveteaching.com/writesci/Rebops/ Objective: To explore the process of meiosis from chromosome segregation and gamete formation to gamete recombination to determination of genotype and resulting phenotype. National Standards:


Background knowledge: Students should have a general understanding of the difference between meiosis and mitosis and what the purpose of each is. Students should also have knowledge of what an allele is and a basic grasp on the terms genotype and phenotype as well as the idea of inheritance. Other helpful background knowledge would include familiarity with the terms heterozygous and homozygous. Materials needed:

• Set of chromosomes made from colored paper o Male (Green) & Female (Yellow)

32 strips of paper total (4 each - 11, 10, 8, 5, 4, 3, 2, &1” long x 1”wide) – divide into two matching sets (2 of each length).

Both parents are heterozygous so write one capital letter and one small letter on each pair of chromosomes; make two identical sets.

• Large marshmallows (body and head) • Small colored marshmallows (humps, nose)

A a Q q E e D d M m T t L l X X

or Y

Create two heterozygous chromosome sets for each the male and female – 4 sets total.

• Colored toothpicks (ligaments/bones, legs, antenna) • Pipe-cleaners (tails) • Thumb tacks (eyes) • Handouts – Marshmallow Meiosis, Stages of Meiosis

Procedures:

1. Prepare the chromosome sets or if the class is advanced enough they can make their own.

2. This activity seemed to work best in pairs or groups of three. Each pair would create one set of gametes and then depending if they had a male or a female they would search out a Reebop of the opposite sex to mate with.

3. Depending on the student’s level of understanding and knowledge of meiosis it may be helpful to provide the students with a diagram of meiosis that they can follow along.

4. Begin the activity by explaining how these new creatures called “Reebops” have been discovered. They have 8 chromosomes (2n=16) and are diploid just like humans (2n=46).

5. You have been fortunate enough to capture 2 heterozygous Reebops; one male and one female. It is the student’s job to simulate meiosis for these two parents and determine what their progeny may look like.

6. The students will then use the heterozygous set of chromosomes you have made to practice the process of meiosis and create four gametes for their Reebop. After creating the four gametes they each pick one and discard the rest (push to the side of the table). Have the students record their set of alleles.

7. Then they need to find a Reebop gamete of the opposite sex to combine with. After they acquire this information they can determine their genotype and from that determine the phenotype of their Reebop using the secret decoding chart.

8. After they have determined the phenotype allow the students to construct their baby Reebop using marshmallows, toothpicks, pipe-cleaners, etc.

Extensions/Variations: There are a lot of different ways to approach this lab depending on what you want your students to learn from it and how well they understand the material going into the activity.

• Add or subtract chromosomes • Change mode of inheritance/phenotypes • Model recombination, mutation, or nondisjunction

Name: Date:

Marshmallow Meiosis – Handout For Teacher – answers in bold

A new species called Reebops has recently been identified in the area. Not much is known about

these unique animals; however genetic analyses have revealed that Reebops (2n=16) are a

diploid species just like humans (2n=46).

How many chromosomes are in a Reebop somatic cell? 16

How many chromosomes are in a Reebop gametic cell? 8

We have been fortunate enough to capture two Reebops; a male and a female. Both the male and

the female have been determined to be heterozygous at all loci.

What does “heterozygous at all loci” mean? Two dissimilar alleles coding for every gene in a

genotype

There has been quite a bit of success in mapping the Reebop chromosomes. In fact an

observable phenotypic characteristic has been mapped to each of the chromosomes. A chart

revealing the phenotype of the genetic code is attached. This will make it possible to visualize

possible progeny of the Reebops we have captured.

The Reebop has eight pairs of chromosomes. How many chromosome combinations are possible

from an organism that has eight pairs of chromosomes? 2^8

You have been given a representation of both the female and male Reebop chromosome sets. It

is your mission to create gametes through simulation of meiosis and determine the phenotype of

the baby Reebop you have developed.

The Reebop chromosomes have been numbered from 1 to 8 from longest to shortest. Record the

allele(s) you have in your gamete for both your female and male.

1 2 3 4 5 6 7 8

1 2 3 4 5 6 7 8

When these two gametes are combined via fertilization what is the resulting genotype of the

progeny created? Using the phenotype coding chart provided what is the phenotype of your

baby Reebop?

Chromosome Genotype Phenotype

1

2

3

4

5

6

7

8

1 AA 1 antenna

1 Aa 2 antenna

1 aa No antenna

Incomplete Dominance

2 MM 1 green hump

2 Mm 2 green humps

2 mm 3 green humps


3 QQ Red nose

3 Qq Orange nose

3 qq Yellow nose


4 TT or Tt Curly tail

4 tt Straight tail Complete Dominance

5 EE or Ee 2 eyes

5 ee 3 eyes Complete Dominance

6 LL or Ll Blue legs

6 ll Red legs Complete Dominance

7 DD or Dd 3 body segments

7 dd 2 body segments Complete Dominance

8 XY Male

8 XX Female Incomplete Dominance

Handout Stages of Meiosis

http://www.bbc.co.uk/schools/gcsebitesize/biology/cellprocesses/celldivisionrev3.shtml

http://www.bbc.co.uk/schools/gcsebitesize/biology/cellprocesses/celldivisionrev3.shtml

Lesson 5

Transcription and Translation

DNA to Protein

Objective: Simulate the processes of transcription and translation using the provided materials. Grade Level: 9-12 National Standards:


Background Knowledge: Organisms use DNA as there permanent source of “knowledge” for functioning throughout their lives. As cells grow and their environment changes different genes may need to be “turned on” in response to a stimulus. Turning on a gene begins the process of transcription and translation to make functional proteins that help the organism to survive and/or react to their surroundings. This is a complicated process however, this activity is designed to create a balance by displaying most of the intricacies of the process but also simplifying it to a level the students can understand. For this activity, we will use Velcro as the DNA and RNA and paper clips for the amino acids. Vocabulary:

• Transcription: the process of transcribing DNA to messenger RNA

• Translation: the process of translating messenger RNA to protein (amino acids).

• 5’ end: end of DNA on which transcription ends and end of RNA which translation begins.

• 3’ end: end of DNA on which transcription begins and end of RNA which translation

ends. • Codon: three letter code on the messenger RNA that codes for an amino acid

• Anti-codon: three letter code on the transfer RNA that matches a codon on the messenger

RNA

• Coding region: a portion of DNA (or messenger RNA) that contains a sequence that codes for a protein

• Initiation codon: a codon (AUG) that begins the translation process from messenger

RNA to protein

• Termination codon: a codon (UAA or UAG) that stops the translation process from messenger RNA to protein

• Point mutation: a single nucleotide change (e.g. from A to T)

• Frame shift: when the ribosome shifts over and begins reading in a different frame (from

reading AUG CGA ATT to reading UGC GAA TT) Materials:

• Velcro – chromosomes nucleotides anticodons

• Duct tape (to attach nucleotides to each other) • Paper clips (amino acids) – 20 different colors (How many amino acids are there?) • Reference Materials

Procedures:

1. Carefully read through these instructions and check off each step as you go. 2. Discuss in your group how transcription and translation occur; think about all of the

organelles and components that are necessary for transcription and translation to occur (your vocabulary list on the first page may be a good starting point… but not a complete list). Jot down the ideas your group forms. 3. Write-up a procedure that you will use to simulate the processes. Try to be as specific as possible about all steps involved and describe them in detail in your write-up. Be sure to assign each group member a role in the process and record their role as part of your procedure write-up.

4. Important things to remember include: What are the start sequences? What are the stop sequences? Which direction does transcription occur? Which direction does translation occur? Where in the cell does each activity occur?

5. Practice transcription and translation using the procedure your group has worked out. 6. Answer these questions (as a group) and include in your final write-up:

a. How do the activities, transcription and translation (that a cell carries out), relate to the mapping, sequencing, and understanding of genomes? b. Mutations can be very detrimental to an organism. What checks do transcription and translation have to attempt to prevent these detrimental mutations from occurring?

7. If time permits we will exchange procedures to compare how other groups approached the processes.

Assignment:

Complete the above activity and have one group member type your procedure including steps 2, 3, 4, and 5.


As the codon As the anti-codon CCC Proline Glycine CCU Proline Glycine CCA Proline Glycine CCG Proline Glycine CUC Leucine Aspartic Acid CUU Leucine Aspartic Acid CUA Leucine Glutamic Acid CUG Leucine Glutamic Acid CAC Histidine Valine CAU Histidine Valine CAA Glutamine Valine CAG Glutamine Valine CGC Arginine Alanine CGU Arginine Alanine CGA Arginine Alanine CGG Arginine Alanine ACC Threonine Tryptophan ACU Threonine None ACA Threonine Cysteine ACG Threonine Cysteine AUC Isoleucine None AUU Isoleucine None AUA Isoleucine Tyrosine AUG Methionine (initiation) Tyrosine AAC Asparagine Leucine AAU Asparagine Leucine AAA Lysine Phenylalanine AAG Lysine Phenylalanine AGC Serine Serine AGU Serine Serine AGA Arginine Serine AGG Arginine Serine UCC Serine Arginine UCU Serine Arginine UCA Serine Serine UCG Serine Serine UUC Phenylalanine Lysine UUU Phenylalanine Lysine UUA Leucine Asparagine UUG Leucine Asparagine UAC Tyrosine Methionine UAU Tyrosine Isoleucine UAA Stop Isoleucine UAG Stop Isoleucine UGC Cysteine Threonine UGU Cysteine Threonine UGA Stop Threonine UGG Tryptophan Threonine GCC Alanine Arginine GCU Alanine Arginine GCA Alanine Arginine GCG Alanine Arginine GUC Valine Glutamine GUU Valine Glutamine GUA Valine Histidine GUG Valine Histidine GAC Aspartic Acid Leucine GAU Aspartic Acid Leucine GAA Glutamic Acid Leucine GAG Glutamic Acid Leucine GGC Glycine Proline GGU Glycine Proline GGA Glycine Proline GGG Glycine Proline


From: http://www-stat.stanford.edu/~susan/courses/s166/node2.html


http://allserv.rug.ac.be/~avierstr/principles/pcr.html

Lesson 6

Animal Genetics

Objective:

• Students will understand how Punnett Squares work. • Students will understand the relationship between genotypes and phenotypes. • Students will explore how limited alleles produce genetic diversity.

Grade Level: 6-12 National Standards:


Background Knowledge: Students should be familiar with Genotypes and Phenotypes and have some notion of heredity. Materials Needed:

• Dice • Marker/Crayons • Animal Genetics Worksheets

Vocabulary:

• Allele – one form of a gene. • Loci – location of a gene on the chromosome. • Diploid – having two copies of each chromosome, therefore having two alleles

for each gene. • Genotype – set of alleles for a given gene. If diploid, 2 letters Tt, aa, etc. • Phenotype – expressed (visual) form of the gene. Tall plant, Purple skin, O blood

type, etc. • Polymorphism – a gene having more than two common phenotypes. Red, pink,

and white. • Homozygous – having two identical alleles for a specific loci. Can be either

homozygous dominant (AA) or homozygous recessive (aa). • Heterozygous – have two different alleles for a specific loci (Aa). • Hybrid – same as heterozygous. • Complete dominance – dominant allele is always expressed and recessive

phenotype will only be expressed if homozygous recessive. TT or Tt = tall and tt = short.

• Incomplete dominance – both alleles are responsible for resulting phenotype. RR = red, Rr = pink, rr = white.

• Punnett Square – this is used for predicting crosses for a specific trait. • Multiple loci phenotypes – traits in which several different loci are responsible

for the phenotype. • P generation – parental generation, • F1 generation – first filial generation (first cross). • F2 generation – second filial generation (second cross).

Procedure: This series of activities have been created to help students master using a Punnett Square. 1. In Advance: Draw the Parent Animals based on the Punnett Squares on the worksheet

(Mom is across the top, Dad is on the left) 2. Model completing the first Punnett Square on the board or an overhead. Complete the

square, identify which square is being used (based on a roll of the dice) and figure out the genotype and phenotype.

3. Give each student a die (they will have to share for the dihybrid crosses if you are

doing cows or horses). Have the students roll the die one time and stop. If they have rolled between a 1 and 4, have them write their number in the blank for dice roll for the first trait. If they rolled a 5 or a 6 they need to roll again until they get between 1 and 4. Have the students do all their dice rolling at once so that you can collect the dice and no more noise.

4. Have students complete the Punnett Squares. 5. Have students draw a picture of the animal their worksheet produced. (For students

who do not like to draw having a blank outline for them to use helps.) 6. Display all the drawings. This is the first generation from one set of parents. The class

can make observations about the frequency of traits and diversity, recessive and dominant traits can be discussed.

Extensions: • Have the kids proceed through and make a second generation. • Comparison of theoretical and actual phenotypic ratios can be calculated. • Other questions can be asked to get the students to think about how the information

can be used for agricultural and scientific reasons.


Sample Student Worksheet- Cats

Name: ______________________

Fill in the missing information for each trait. After you have determined all the traits your kitten will have, make a drawing of your cat. Name your cat and write a description of your cat that includes all of the phenotypes it received from its parents.Complete Dominance TraitsTrait #1: StripesWhite stripes (W) is the dominant trait. No stripes (w) is the recessive trait. Parent #1 is a hybrid with white stripes (Ww) and parent #2 has no stripes (ww).

43

21w

w

w

WDice roll = ______

Kitten genotype = ______

Kitten phenotype =

____________________

Trait #2: Tail lengthNormal tail (N) is the dominant trait. Bobbed tail (n) is the recessive trait. Parent #1 is a hybrid with normal tail (Nn) and parent #2 has a bobbed tail (nn).

43

21Dice roll = ______


Kitten phenotype =

____________________

Trait #3: Ear shapePointed ears (P) is the dominant trait. Rounded ears (p) is the recessive trait. Parent #1 is a hybrid with pointed ears and parent #2 is a hybrid with pointed ears.

43



Kitten phenotype =

____________________

Genotype Phenotype

WW White stripes

Ww White stripes

ww No stripes

Genotype Phenotype

NN

Nn

nn

Genotype Phenotype

Trait #4: GenderThe father is male (XY). The mother is female (XX).

43



Kitten phenotype =

____________________

PhenotypeGenotype

n

n

n

N


Incomplete Dominance TraitsTrait #5: Nose ColorIn this case, each genotype produces a different phenotype since the dominance is incomplete. Both parents have a spotted nose.

43

21

Trait #6: Fur lengthIn this case, each genotype produces a different phenotype since the dominance is incomplete. Both parents have medium length fur.

43



Kitten phenotype =

____________________

Trait #7: Eye colorIn this case, each genotype produces a different phenotype since the dominance is incomplete. Both parents have green eyes.

43

21

Dice roll = ______ & ______ Kitten genotype = ______ Kitten phenotype = ___________

Genotype Phenotype

BB Black

Bb Spotted

bb Pink

43

21

Co-dominant trait with 2 genesTrait #8: Fur colorIn this case, each genotype produces a different phenotype since the dominance is incomplete. Both parents have brown fur. Gene #1 is F and Gene #2 is P.

43

21

Dice roll = ______


Kitten phenotype =

____________________

Purpleffpp

GrayffPp

GreenffPP

OrangeFfpp

BrownFfPp

BlackFfPP

BlueFFpp

TanFFPp

PinkFFPP

PhenotypeGenotype

Genotype Phenotype

LL Long fur

Ll Medium fur

ll Short fur

Dice roll = ______


Kitten phenotype =

____________________

Genotype Phenotype

BB Brown

Bb Green

bb Blue

Gene #1 Gene #2

Lesson 7

Fruit Fly Ranching … Student Outcomes/Objectives

• to gain a better understanding of genetics and its application to a particular organism (in this case Drosophila – the common fruit fly) • to gain a better understanding of the Punnett Square and applying this knowledge to find combinations of desirable traits • to become familiar with and gain experience in running a business • to be exposed to the idea of business proposals, loan approval forms, business ledgers, using checks, and dealing with income taxes

National Standards:


Background Knowledge: This lesson plan combines both science and business to form a fun and active classroom project. This lesson plan is an excellent way for students to take what they learn in the classroom and apply it to the real world.

Material

• Drosophila • Plastic Vials w/ foam stoppers • Growing Medium • Q-Tips • Fly Nap • Ledger Forms • Loan Approval Forms • Check Forms • Masking Tape • Grease Pencil/Marker • Candy/Prizes • Price Sheet Forms • Magnifying Glass

Worksheets Fruit Fly Ranch Loan Paperwork

My Fruit Fly Ranch Example Result Form

Teacher Keys *Italicized words in lesson plan are potential script for teacher (add this if teacher scrip is

included in lesson plan)

Fruit Fly Ranching

Fruit Fly Ranch Activity

Procedures

1. This is a culminating inquiry-based activity that follows a discussion of the basics of genetics. The students should be familiar with the terms Genetics, Heredity, Traits, Genotype, Phenotype, Punnett Squares, Generations, Offspring, Monohybrid, Dihybrid, and Genotypic/Phenotypic Ratios. The students should also be familiar with the traits of Drosophila.

2. After our discussion of genetics, the students are shown a number of vials containing

Drosophila. The students are then asked what traits the flies have in common and some traits that are different. After the students have composed the list, each student is given a price sheet of the value of certain combinations of traits.

3. Without instruction or guidance the students are then assigned to raise fruit flies on their

own ranch in order to earn as much money they can by selling the flies that they have raised. However before the student may begin, each student must submit a one-page “Business Proposal” to the bank in order to borrow money to get his or her business started. The proposal should include the name of the ranch, materials needed, the purpose of the loan, what parents will be used, what is the expected outcome, a timeline of anticipated events and a schedule of payback for their loan. Also have the students budget a little extra money in case of unforeseen expenses.

4. Once a proposal has been approved, the student is asked to sign a contract with the bank

and checks are issued (Loan Approval Form). It is also necessary to discuss with the students what checks are used for, how they work and how a check is filled out. It is a good idea to have the students practice writing the checks at this time.

5. Another item that is given to the student is a business ledger. This is used to track the

income and expenses of the ranch. Again this it is vital to discuss the differences between income and expenses and have the students practice keeping track of these items using the Ledger Forms. Each student is required to keep a running balance of the money in their accounts and each has a file folder with their names on them. Be sure and occasionally check their balances with the banks balances to make sure they don’t bounce checks. If a student bounces a check, normal bank fees apply. This may mean that the student will have to borrow more money.

6. It is time for the students to begin raising their flies. The students need to purchase their

supplies and materials (using checks) and create a home for their flies. Be sure that instructions for preparation of growing medium are given.

7. After the growing medium has been prepared, the students will now wait for their flies to

grow. Every couple of days the students are required to check on their vials and note changes that occur within.

8. Once the flies have matured and emerge, the flies will be put to sleep using the fly nap

and q-tip. The students will then use a magnifying glass to separate the flies with the different traits, i.e. eye color, wing shape and to count the number of each. The flies will then be counted and assigned a value by the teacher and this will give the students their gross income.

9. After the students have found out how much money they have earned, they are then asked

to repay the balances of their loans. Finally the idea of income taxes is introduced. Depending on the amount that they student earned, they are assigned a tax bracket and are asked to write a check to state and federal agencies for their taxes. This will give us the student’s disposable income. This is the amount that the students are allowed to spend for prizes following the activity. Prizes can include candy, toys, classroom supplies, periodic tables, hall passes, homework passes, etc.

Assessment There are a variety of ways to assess the students for this activity. Ideas are counseling peers on how to make more money, rewriting their business proposal so that they could make more money if the activity were repeated, posters of their experiments and results or merely having the students write what they have learned from the activity.

Fruit Fly Ranch Loan Paperwork

Date: _______

Regarding: Loan for (Ranch Name)

Dear Mr. / Ms. (Student Name)

This letter is to inform you that your loan has been granted.

We look forward to seeing your business venture grow and be very successful. We are here to assist you in any way possible. Please note that you must pay us back in a timely manner. Your total loan must be paid back after your 5th payment. Please see below for your loan costs.

Loan Amount $ 445.00

Interest (10%) $ 44.50

Payment Amt $ 61.19

Balance due after 5th Payment $ 183.56

I have read and understand the terms of the above agreement.

I promise to make all payments on time, if I do not pay on time I could be charged a late fee.

Signed: _________________________________________ __________________________Rancher Bank Manager

Name ___________________

My Fruit Fly Ranch

Date Activity Income Expenses Balance Opening Balance $ 400.00 $ 400.00

Example Result Form

Tax Rate

Tax Amount Total Gross Less Loan Payment

Net Amount

Dustin $1,210 0 $0 $1,210 $ 647.62 $562 Michael $2,045 0.1 $205 $1,841 $ 435.00 $1,405.50 Lindsey $2,255 0.1 $226 $2,030 $ 330.00 $1,699.50 Andi $2,315 0.25 $579 $1,736 $ 428.31 $1,307.94 Yessenia $2,770 0.25 $693 $2,078 $ 302.04 $1,775.46 Ben $3,920 0.35 $1,372 $2,548 $ 529.24 $2,018.76 Zack $3,630 0.35 $1,271 $2,360 $ 369.60 $1,989.90 Naomi $4,100 0.4 $1,640 $2,460 $ 301.24 $2,158.76 Julia $4,755 0.4 $1,902 $2,853 $ 395.00 $2,458.00 Michael $9,230 0.45 $4,154 $5,077 $ 1,052.70 $4,023.80 Jarred $16,282 0.45 $7,327 $8,955 $ 690.62 $8,264.48

Lesson 8

DNA Extraction

Objective: Students will learn how to extract DNA from living sources using household reagents National Standards:


Background knowledge: Students should have a general knowledge of what DNA is and cell structure. Materials needed:

• DNA sources (wheat germ, apple, onion, kiwi, potato, beef liver) • Soap (liquid dish soap) • Salt • Enzyme (meat tenderizer) • Room temperature water • Alcohol (97% EtOH) • Plastic test tubes with caps • Knife to cut DNA sources • Mortar and pestle (to macerate samples) • Gauze • Funnel • Small beaker (to transfer EtOH in to test tubes) • Disposable plastic pipettes (to dispense soap) • Wooden skewers

Procedure: It is best if you can have small chunks of DNA sources cut up for the students and kits with everything they need set out at their lab stations. This prevents a lot of chaos and “lost” reagents during the lab. Either provide the students with a set of directions or have them write the procedure up themselves. Be sure to discuss what role soap, meat tenderizer, and alcohol may play in the extraction.

1. Macerate your DNA source with a mortar and pestle.

2. Mix macerated sample with a pinch of salt and tap water (2x the volume of the sample) to create a “cell soup”.

3. Strain the soup using gauze in a funnel into a test tube. The test tube should be half-full at maximum. Discard anything more than half of the test tube volume.

4. Add detergent (~1/6 the volume of the strained soup volume). Replace tube cap and swirl gently or gently invert the tube to mix. Try to create as few bubbles as possible. Let this mixture set for 7-10 minutes.

5. Add a pinch of enzyme (meat tenderizer) to test tube; swirl gently – being too rough will break DNA making it difficult to see.

6. Tilt the test tube and slowly add an equal volume of iced EtOH. 7. Tilt the test tube back upright and watch for a layer of DNA to form (between water and

alcohol layers). 8. Use a wooden skewer or glass rod to hook the DNA into the alcohol and cause further

precipitation. Extensions/Variations: Many extensions and variations can be done with this lab.

1. Provide both living and nonliving sources and see what you can extract DNA with. 2. Try different reagents (different soaps, different enzyme sources like pineapple juice or

contact solution, etc.) and see if you can achieve the same results. Additional lesson: DNA Jewelry – Resource: http://www.fresno.k12.ca.us/schools/S090/_atkinsgatebio/beadproject/GenJewelProjCtr.html

Name____________________________

Date_____________________________ What do you already know

about DNA? What do you want to know

about DNA? What have you learned

about DNA?

1. Where is DNA found?

2. Do all living things have DNA?

3. Who first proposed the double helix structure of DNA and when did they do it?

4. DNA is composed of nucleotides. What is a nucleotide?

5. The base pairing rules are very important in DNA replication.

a. What are the 4 bases in the DNA molecule?

b. What bases pair together?

c. How does this help DNA replicate?

6. What is the difference between DNA and RNA?

7. What is a chromosome?

8. What is a histone? What would happen if no histone was present?

9. ____________ occur when changes in genetic information occur due to alteration in the DNA sequence.

10. Complete the polypeptide sequence based on the DNA sequence: ATGATTCCTGTGGGT

11. Draw and label a DNA molecule. 12. How can polyploidy in plants benefit humans?

Teacher Copy Name____________________________

Date_____________________________ What do you already know

about DNA? What do you want to know

about DNA? What have you learned

about DNA?

1. Where is DNA found? In all living things

2. Do all living things have DNA? YES

3. Who first proposed the double helix structure of DNA and when did they do it? Watson and Crick; 1953

4. DNA is composed of nucleotides. What is a nucleotide? A phosphate molecule attached to a sugar molecule; these molecules are linked together to for a DNA or RNA strand; aka A, G, C, and T in DNA or A, G, C, and U in RNA.

5. The base pairing rules are very important in DNA replication. a. What are the 4 bases in the DNA molecule?

Adenine (A), Guanine (G), Thymine (T), Cytosine (C)

b. What bases pair together? A-G C-T

c. How does this help DNA replicate?

Unwound strands of DNA reveal a single strand of nucleotides which serve as a template for new DNA

6. What is the difference between DNA and RNA?

i. Both DNA and RNA consist of a long chain of nucleotides ii. DNA contains the base thymine (T), not uracil (U)

iii. RNA contains the base U, not T

7. What is a chromosome? Structure which contains genetic factors as DNA (or RNA) arranged in linear order

8. What is a histone? What would happen if no histone was present?

The protein DNA wraps around in eukaryotic chromosomes; No double helical structure

9. ___Mutations___ occur when changes in genetic information occur due to alteration in

the DNA sequence.

10. Complete the polypeptide sequence based on the DNA sequence: ATGATTCCTGTGGGT

Met – Ile – Pro – Val – Gly ___

11. Draw and label a DNA molecule. 12. How can polyploidy in plants benefit humans?

- Improved yields - Seedless fruits

Lesson 9

Gel Electrophoresis

Protocol for Pouring, Loading, and Running a DNA Agarose Gel

Objective:

Students will learn how to pour load and run an agarose gel

National Standards: • Students should develop an understanding of reproduction and heredity • Students should develop understanding of molecular basis of heredity

Pouring a Gel

Materials

• 0.45 g Agarose • 45 ml 1 x TBE • Gel Tray • Lab tape • Plastic wrap • Well comb

Procedure

1. Tape sides of gel try to prevent Agarose from leaking

2. Make sure tray is on a level surface

3. Add measured Agarose powder to a flask

4. Add measured 1 x TBE to flask

5. Swirl to mix

6. Cover with plastic wrap. Poke holes in plastic wrap with a pipette tip (to allow steam to

escape, but prevent loss of liquid)

7. Heat on a hot plate until Agarose is dissolved (~ 12 min on high)

8. Swirl solution occasionally during heating

9. Let solution cool until you can touch it

10. Pour into prepared gel tray with comb in place

11. Check for bubbles and use a pipette tip to pop any found

12. Let solidify (~30 minutes depending on the size of the gel)

13. If not using your gel immediately, store at RT in 1X TBE solution

Loading a Gel

Materials

• Solidified Gel • Electrophoresis • 1X TBE • DNA Samples • Standard

Procedures: 1. Place the tray with the solidified gel into the electrophoresis box

2. Make sure the whole gel is just covered with 1x TBE

3. Carefully, remove the comb while holding the tray in place

4. Load the measured amount of sample into the well and brace your hand if necessary

∗ Depending on the size of the well load 5-15 μL total volume. The sample should

include loading dye. Loading dye is made mostly of sucrose and a dye. The sucrose

weighs down the DNA sample so it drops to the bottom of the gel well and the dye

allows for visualizing how far the samples have traveled down the gel. Depending on

the size of the sample add between 1-3 μL of loading dye.

∗ Loading dye has been added to some samples during the extraction procedure. Some

samples may require you to add dye to samples before loading in the gel.

Running a Gel

1. Place the top of the electrophoresis unit onto the box making sure that the contacts are

appropriately connected (black to black, red to red)

∗ Have the negative electrode at the well end of the gel. DNA is negatively charged.

Opposites attract and likes repel so with negative DNA at the negative electrode the

DNA will travel away from the negative current and toward the positive current.

2. Plug the unit into the power source (again: black to black, red to red)

3. Turn unit on, set to desired voltage, begin run

4. Run ~ 20 min @ 200V or 40 min @ 100V; you can determine how far the gel has run by the

distance the loading dye has gone.

5. Turn power unit off before disconnecting the apparatus.

Alternative Staining Procedure using Methylene Blue

∗ This procedure is non-hazardous and you can visualize the fragments on a simple light box.

Limitations of the methylene blue technique are: less sensitivity (requires more DNA) and

requires a longer staining and destaining times to visualize the DNA fragments

1. 0.025% Methylene Blue Procedure

a. Flood gel with 0.025% methylene blue (dilute 0.1% methelyne blue 50μL with

ddH2O (200mL)), stain 20-30 minutes or continue staining overnight at 4C.

b. The next day place the stained gel in clean water and rinse until gel is destained;

Let gel soak for several minutes in several changes of fresh water. DNA bands

will become increasingly distinct as gel destains. You may continue to destain

overnight in a small volume of water if necessary. (Gel may destain too much if

left overnight in large volume of water.)

c. Cover staining tray to retard evaporation.

d. View gel over light box; cover surface with plastic wrap to prevent staining.

2. 0.1% Methylene Blue Procedure

a. Coat gel in 0.1% methylene blue, let stain one minute

b. Destain gel in successive water washes

c. You may continue to destain overnight in a small volume of water if necessary.

(Gel may destain too much if left overnight in large volume of water.)

d. Cover staining tray to retard evaporation.

e. View gel over light box; cover surface with plastic wrap to prevent staining.

(1) The agarose gel with three slots (S). (2) Injection of DNA ladder into the first slot. (3) DNA ladder injected. Injection of samples into the second and third slot. (4) A current is applied. The DNA moves toward the positive anode due to the negative

charges on its phosphate backbone. (5) Small DNA strands move fast, large DNA strands move slowly through the gel. The

DNA is not normally visible during this process, so the marker dye is added to the DNA to avoid the DNA being run entirely off the gel. The marker dye has a low molecular weight, and migrates faster than the DNA, so as long as the marker has not run past the end of the gel, the DNA will still be in the gel.

(6) The DNA is spread over the whole gel. The electrophoresis process is finished.

Figure from: http://en2.wikipedia.org/wiki/Agarose_gel_electrophoresis

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