There’s a Small World Out there
Part 4: Understanding DNA and Biotechnology
PURPOSE: To understand the role of DNA in the field of biotechnology. To understand the importance of biotechnology for NC.
GOAL/OBJECTIVE
Goal 1 –The learner will design and conduct investigations to demonstrate an understanding of scientific inquiry.
Objectives 1.01, 1.05, 1.08, 1.09, 1.10
Goal 7 – The learner will conduct investigations, use models, simulations, and appropriate technologies and information systems to build an understanding of cell theory.
Objective 7.05
Language (ELD) Objective: The learner will -
ENGAGE:
Use the following questions to guide a class discussion and review for students to understand that DNA is like a recipe that gives instructions for how to create and maintain a living organism. You can lead a class discussion where you record
responses, ask the students to complete a KWL chart with the questions, or have the questions on posters to use as a walkthrough. Revisit the questions as you go through this part of the unit. At the end of the unit, ask the students to respond to the questions again.
1. What is a recipe?
2. How many of you have followed a recipe to make something?
DNA is not visible to the eye unless you have a large quantity, which can be obtained by extraction from a considerable number of cells. Extracted DNA can be used for genetic testing, identification of human bodies, and analyzing forensic evidence.
Note to teacher: You will need to prepare the buffer solution ahead of time for the following activity (see recipe below).
Recipe for buffer solution:
To make one liter, mix 100 ml clear shampoo without conditioner, 15 g NaCl, 900 ml water.
Use the attached worksheet with directions for the students to extract DNA from a strawberry. Ask the students to complete the worksheet for the DNA extraction as they complete the activity. The extracted DNA can be stored in a micro-centrifuge tube. The students keep the DNA. Be sure to discuss the lab after the students have finished.
Discussion: The strawberries must be mashed in order to break down the cell walls and nuclear membranes. The buffer solution is added because the salt helps the DNA precipitate when the alcohol is added. The dish detergent releases the contents of the cell into the solution. The alcohol is added slowly to help the DNA separate from the solution. The resulting “snotty” substance is millions of strands of DNA.
Optional Activity #1: DNA has a unique structure known as a double helix, which is shaped like a twisted ladder. Ask the students to research to find out who discovered this structure of DNA, and then present their findings in a multimedia presentation, poster, or brochure.
Next, review the structure of a cell. Discuss the organelles and location of DNA within the nucleus. Then, have the students explore the structure of DNA further by making a 3-D model. Their model should include the 4 base pairs (thymine, adenine, cytosine, and guanine), the sugar molecules, and phosphate groups. The students need to make a key to show what each part of the model represents. Students should be ready to show their model and explain the structure.
Optional Activity #2: You can make DNA necklaces with hemp twine and micro-centrifuge tubes of their stored DNA extracted from the strawberries. Directions for making the necklace can be found at the following site:
http://www.ehow.com/how_152_make-hemp-necklace.html
As you make the necklace, you will notice that it twists like the DNA ladder. It resembles a strand of DNA. After you extract your strawberry DNA, place a small amount in a micro-centrifuge tube and seal it with super glue or a hot glue gun. Thread your hemp through the loop on the micro-centrifuge tube.
EXPLAIN:
Use the PowerPoint presentation “History of Biotechnology” (found in the “instructional resources” box) and the attached student notes sheet to show the history of
biotechnology and how advancements in technology have been made in this field. After you view the PowerPoint and take notes, ask the students if see any trends or patterns in how the science of biotechnology has developed.
Background Information for teachers and students: The structure of DNA in all living things is consistent. However, the specific sequence of base pairs within a DNA molecule differs between organisms in order to create “blueprints” for the individual species. This sequence of base pairs is what makes an organism a maple tree or a horse, a male or a female, etc.
Every time a cell divides, it must make an exact copy of its DNA to be distributed to the daughter cells. This replication ensures that each daughter cell has the genetic
information it needs to carry out its activities. The two sides of the DNA “ladder” are made up of alternating phosphate groups and sugar molecules. Each of the steps of the “ladder” is made of a complimentary pair of nitrogen bases. The bases are thymine, adenine, cytosine, and guanine. Adenine and thymine will always pair together, and cytosine and guanine will always pair together. When DNA is ready to copy itself (replication), the two sides of the DNA ladder unzip down the middle of the bases. With the help of special enzymes, nucleotides present in the nucleus pair up with their
compliment on each side of the DNA “ladder.” The order of the bases in the two new “ladders” exactly matches the DNA in the original “ladder.” Use one of the student models to explain the structure of DNA.
ELABORATE:
Copies of A Million and One, a brochure about careers in microbiology designed for pre-college and undergraduate students, are available from the ASM Board of Education. (A Spanish version is available as well.) To receive up to 25 free copies, email [email protected] or fax your request to 202-942-9329. Be sure to include your mailing address with your request and indicate if you want the English or Spanish version.
Additional Resources
http://www.cdc.gov/excite/careers/index.htm Careers in public health
http://science.education.nih.gov/LifeWorks.nsf/feature/index.htm Careers in science
ENGAGE, Part 4 Name ___________________________________
Handout Date ____________________________________
Discuss and answer the following questions with your group members.
1. What is a recipe?
2. How many of you have followed a recipe to make something?
3. When you follow a recipe, did you have certain ingredients that you used? Why?
4. What do we call “the recipe” for your body?
5. How do you think a recipe is like DNA?
6. What are the ingredients of DNA?
7. How does the recipe for your DNA compare to that of your family members?
EXPLORE, Part 4 Name ___________________________________ Handout Date ____________________________________
DNA Extraction
Answer the following before you extract the DNA:
1. What kind of tools or equipment would you use to remove a wall in a building? ________________________________________________________________ ________________________________________________________________
2. If you knew what the wall was made of, would it help you to decide what tools or equipment to use? Explain.
________________________________________________________________ ________________________________________________________________
3. Think about chewing on a carrot. Your teeth have to break open the cell walls of the carrot cells. How could you break through the cell walls of your strawberry? ________________________________________________________________ ________________________________________________________________
How to extract DNA from a strawberry: 1. You will need:
1 strawberry, fresh or frozen 10 mL DNA extraction buffer
1 heavy-duty zip-lock bag ice cold 91% alcohol or 95% ethanol 1 round, coffee filter coffee stirrer or stick
1 5 oz. cup
2. Place one strawberry in a zip-lock bag. Mash the strawberry for 2 minutes. 3. Add 10 mL of extraction buffer to the bag. Mash again for 1 minute.
4. Place the coffee filter over the cup and press down in the middle to form a well. Fold the edges of the coffee filter over the side of the cup and hold it. Filter your strawberry mixture through the coffee filter. Be careful so that the pulp and seeds do not go into the cup. You should have about 1 tablespoon of filtrate in the bottom of the cup.
5. Slowly add ice cold alcohol to the filtrate to equal 3 times as much liquid. 6. Do not mix the filtrate and the alcohol. You will see the DNA strands begin to
clump together in the solution and float toward the top. You can then carefully spool the DNA on your coffee stirrer and place it in a micro-centrifuge tube to observe.
Answer the following after you extract the DNA: 1. What materials were trapped in the coffee filter?
________________________________________________________________
2. What materials passed through the coffee filter?
3. Describe the appearance of your extracted DNA.
________________________________________________________________ ________________________________________________________________ ________________________________________________________________
4. What does mashing the strawberries do to their cells?
________________________________________________________________
5. What does adding the buffer to the strawberries do to the cells?
________________________________________________________________
6. Do you think DNA from an animal cell would look the same as the plant DNA? Explain.
________________________________________________________________ ________________________________________________________________
7. Give an example of something that scientists can do with extracted DNA.
EXPLORE, Part 4 Name ___________________________________ Handout Date ____________________________________
Design Your Own DNA Molecule
TASK: Your challenge is to make model of a DNA molecule. You must research the structure of DNA. Then, decide what materials resemble the structures. Create a key that shows what each material corresponds to in the actual DNA molecule.
POSSIBLE MATERIALS: Straws
Tape Yarn
Rubber bands Candy
DIAGRAM:
Draw and label your DNA model in the space below.
EXPLORE, Part 1 Name _____________________________
Handout Date
___________________________
Design Your Own DNA Molecule RUBRIC
C R I T E R I A
Possible Points Received PointsResearch of DNA:
Discovery of DNA structure
Student is able to present information on the discovery
of the structure of the DNA molecule.
20
Explanation of DNA structure
Student is able to explain the structure of the DNA
molecule.
20
Design of DNA Model:
Construction of model
Device includes all parts of the DNA molecule - base pairs - sugar molecule - phosphate group - hydrogen bond
40
Creative use of materials
Includes a key for materials used that correlate to DNA
10
Presentation of DNA Model:
Presentation
Student is able to
10
EXPLAIN, Part 4 Name ___________________________________
Handout Date
____________________________________
PowerPoint Notes: “History of Biotechnology”
I. What is Biotechnology?
•
Biotechnology: the branch of molecular biology that studies the use of _________________ to perform specific industrial processes;"biotechnology produced genetically altered ______________ that solved the problem."
II. Biotechnology in B.C.
•
500 BC: The Chinese use moldy curds as an ___________ to treat boils.•
250 BC: The Greeks practice crop rotation to increase ________ ____________.•
100 BC: Chinese use powdered chrysanthemum as an ________.III. Pre-20th Century Biotechnology
•
1590: Janssen invents the _____________. 1663: __________ discovers cells.1675: Leeuwenhoek discovers ________ and __________.
•
1797:Jenner inoculates a child with a viral vaccine to protect him from ___________.•
1802: 1st time the term “_____________” is used.IV. Pre-20th Century Biotechnology
•
1830: ____________, the building blocks of cells, are discovered.•
1833 The _________ of the cell is discovered.•
1855: The E. coli bacterium is discovered.•
1855: Pasteur works with ___________, eventually proving they are living organisms.•
1915: Bacterial viruses, called __________, are discovered.•
1919: The word "____________" is first used.•
1927: Muller discovers that X-rays cause mutation.•
1928: ___________ discovers penicillin.•
1938: The term "molecular biology" is used.•
1941 The term "_________ ______________" is first used.VII. Biotechnology in the First Part Of The 20th Century
•
1942: The electron microscope is used and characterize viruses that infect bacteria, called ___________________.•
1944: __________ is shown to be the building block of the gene.•
1949: ___________ proves that sickle cell anemia is a "molecular disease" caused by a mutation.VII. Biotechnology in the 1950s and 1960s
•
1953: Watson and Crick understand the ____________ of DNA.•
1954: Cell-culturing techniques are first used.•
1955: An __________ involved in the production of a nucleic acid is isolated.•
1956: The fermentation process is perfected.•
1960: Messenger ____________ is discovered.•
1961: The genetic code is understood.VIII. Biotechnology in the 1970s
•
1972: The DNA composition of humans is shown to be ________ similar to that of chimps and gorillas.•
1977: Genetically ___________ bacteria are used to make human growth protein.•
1978: North Carolina scientists, Hutchinson and Edgell, prove it is possible to introduce specific ___________ at specific sites in a DNA molecule.•
1979: The first monoclonal antibodies are synthesized.IX. Biotechnology in the 1980s
• 1980: The U.S. Supreme Court approves the patenting genetically-engineered life forms.
• 1980: The U.S. patent for ____________ ____________ is awarded to Boyer and Cohen.
• 1981: The North Carolina Biotechnology Center is created — the _____ state sponsored research center for biotechnology.
• 1981: The first genetically-engineered plant is reported.
• 1981: 1st mice to be successfully ________.
X. Biotechnology in the 1980s
• 1983: The first artificial chromosome is made.
• 1983: The first genetic markers for specific inherited diseases are found.
• 1984: The DNA ____________ technique is developed.
• 1984: The first genetically-engineered __________ is developed.
1986: The first biotech-derived interferon drugs for the treatment of cancer is synthesized.
• 1988: Congress funds the ____________ ___________ ________.
• 1989: Microorganisms are used to clean up the Exxon Valdez oil spill.
XI. Biotechnology in the 1990s
•
1990: The first federally-approved gene therapy treatment is performed successfully.•
1992: The structure of ________ RT is elucidated.•
1993:The FDA declares that genetically engineered foods are "not inherently dangerous."•
1994: The first ________ _________ gene is discovered.•
1996: Scientists clone identical lambs from early embryonic sheep.XII. Biotechnology in the 1990s
•
1998: Scientists clone three generations of mice from nuclei of adult ovarian cells.•
1998: Embryonic stem cells are used to regenerate _________ and create disorders that mimic diseases.•
1998: The Biotechnology Institute is founded by BIO as an independent national, 501(c)(3) education organization.•
1999: The genetic code of the human chromosome is deciphered.XIII. Biotechnology 2000 and Beyond
• 2000: A rough draft of the human genome is completed.
• 2000: ________ are the next animal cloned by researchers, to help produce organs for human transplant.
ELABORATE, Part 4 Name ___________________________________
Handout Date
____________________________________
Uses of Biotechnology:
Agriculture, Forensics, Political, or Medical Purposes
Directions: Research how biotechnology is used in the area of agriculture, forensics, politics, or medicine. Include the type of research that is performed in your area of choice, the products that have been developed or processes that have been implemented as a result of the use of biotechnology in that area, and the ethical issues associated with the use of biotechnology in that area. Prepare a presentation with your information. You may choose to create a PowerPoint, a informational brochure, or a research board presentation. Use the following rubric to guide you in your research and creating your presentation.
Required Information Possible Points Points Earned and Comments
Research Being Performed in Your Area A clear description of the types of biotechnological research being conducted
in your area of concentration.
20
Products Developed as a Result of Biotechnology
A clear description of 2-3 products/processes that have been developed/implemented as a result of the
use of biotechnology in your area of concentration.
20
Ethical Issues Associated With the Use of Biotechnology in Your Area A clear discussion of the ethical issues associated with the use of biotechnology in
your area of concentration.
20
Presentation
The presentation is neat, organized, and aesthetically pleasing.
20
Sources Sited Appropriately 3-5 sources should be utilized. All sources
should be cited at the end of the presentation in the teacher determined
format.
EVALUATE, Part 4 Name _____________________________
Handout Date
___________________________
Webpage Design:
Economic Benefits of Biotechnology to NC
TASK: You work for the North Carolina Center for Biotechnology in the Public Relations Department. It is your job to create a webpage to inform the public about the economic benefits of biotechnology to North Carolina. You will need to research the topic and design the webpage using Publisher, Google sites, or other webpage software.
PROCEDURE:
1. Look at the following websites or websites you find on your own to find information on biotechnology and the economy of NC.
http://www.ncbiotech.org/ (The NC Biotechnology Center)
http://www.duke.edu/web/mms190/biotech/resources.html (NC and the Global Economy – Biotechnology)
http://chronicle.com/free/v54/i02/02a00101.htm (Article on building NC economy with biotechnology)
2. Complete the research questions. Use the information to create a webpage to inform the public about the role biotechnology has in NC’s economy.
RESEARCH:
Resource Information
Biotechnology organizations in NC
Biotechnology in the food industry in NC
Biotechnology in medicine in NC
Biotechnology and the
economy of NC
RUBRIC:
CRITERIA Points
POSSIBLE
Points AWARDED
Research
40
Webpage Design
• Layout is attractive and easy to follow
• Graphics or photos are used with citations
• Content is accurate and informative
EVALUATE, Part 4 Name ___________________________________
Handout Date
____________________________________
A Career in Biotechnology
TASK: You are about to enter college. You want a career that will allow you to work with microscopes, cells, and DNA.
Your career choice:
_____________________________________________________
PROCEDURE:
1) Look at the following website of biotechnology careers. Select a career that interests you. Decide where you would like to get your training for this career.
* http://www.biotechinstitute.org/careers/
* http://www.biotech.iastate.edu/biotech_info_series/bio2.html * http://www.careervoyages.gov/biotechnology-main.cfm * http://www.accessexcellence.org/RC/CC/
2) Look at the following website for career information.
Occupational Outlook Handbook: http://www.bls.gov/OCO/ 3) Write a career profile for your career.
RESEARCH:
Resource Information
Job
requirements
Job outlook
Expected earnings
Where do you plan to get the training you need for this career?
________________________________________________________________ ______
RUBRIC:
CRITERIA Points
POSSIBLE
Points AWARDED
