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Warm Up
1. What type of cellular transport requires energy?
2. What is the chemical equation for cellular respiration?
3. Where does transcription occur? Where does translation occur?
4. What type of organic molecule is DNA?5. What is the subunit (monomer) of DNA?
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DNA Technolog
y
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Section 1:
DNA Evidence
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DNA Fingerprint
This is what a DNA fingerprint looks like.
This is a real fingerprint – not a DNA print
Gel Electrophoresis – also called DNA Fingerprinting
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Electrophoresis Steps:
1. Restriction Enzymes Cut DNA fragments
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Electrophoresis Steps:2. DNA is placed in wells of the gel (gel is like
jello)
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Electrophoresis Steps:3. Electricity current added, DNA (which is
negative) moves toward the positive end
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Electrophoresis Steps:4. Smaller DNA segments move farther and
faster
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What do we use gel electrophoresis for?
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We can use this to help catch criminals!
We can also determine paternity!
The nitrogen bases in the DNA can be dyed, and this gives us
these bands.
DNA Fingerprinting
DNA Fingerprinting Contd…
• This produces a unique banding pattern following a gel electrophoresis.
• This test is highly accurate, and the probability of another individual possessing an identical banding pattern is estimated as around 1:14,000,000,000.
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DNA Fingerprint & Paternity You get all of your DNA from your mom and dad. Every
band you have must have been inherited from one of your parents.
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Warm Up
1. List 2 ways in which a DNA fingerprint can be helpful.
2. Where would you expect a small segment of DNA to be in a DNA fingerprint?
3. How many daughter cells are produced from meiosis? Are they identical or different?
4. Is mitosis asexual or sexual reproduction?
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Cloning• Clone- a member of a
group of genetically identical cells
• May be produced by asexual reproduction (mitosis)
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Cloning Process1. Egg cell taken from donor and the nucleus is
removed
2. Body cell taken from organism we want cloned. DNA is extracted from this cell.
3. Extracted DNA is put into donated Egg using a vector (a vessel capable of transporting DNA)
4. Fused cell develops into embryo and is placed into a surrogate mother.
5. A clone of the organism who gave us the BODY CELL is born
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Dolly: A Mammal Clone
1997-Dolly was the first cloned mammal.
Died 6 years later due to a progressive lung disease
Why clone?
• Biggest reason: Prevent species from becoming endangered/extinct
• Common endangered animals:– Red wolf, bald eagle, jaguar, manatee, crocodile,
sea turtle, lemur, cheetah, elephant, whales, brown bears
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Endangered Species
• Undercover biologists travel into the meat market and purchase meat• They take it back to their hotel room and run a DNA test
(modified gel electrophoresis) and see if the chromosomes match up for an endangered species
• Then they turn in the people responsible to the police
CLONING Video clip
Shows process of cloning + Diversity of life
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Video Clip 1: So why clone?
• Preserve the diversity of life
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Video clip 2:
What benefits are there of cloning an adult cell rather than an embryonic cell?
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What is cell specialization?
What are transgenics?
What would be a medical benefit of creating a transgenic sheep?
What are your thoughts?
Be prepared to bring ALL of your ideas and questions to the discussion! 26
Should we clone: Plants? Animals?
Humans?
Why or why not?
Individual Activity• Write 5-7 sentences to reflect on our discussion of
cloning today.• Consider the following questions to guide your
reflection:– At the end of this lesson, what is your general opinion of
cloning?– Why do you believe you have this opinion? What sources
have influenced your opinion?– Do you understand why other people might have a
differing viewpoint?
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Cloning Debate-Guidelines• Two choices: AGREE or DISAGREE.• You cannot be in the middle!• If you change your mind at any time, you may
switch to the opposite side but be prepared to talk about why you changed your mind
• Our viewpoints come from various places (culture, religion, political views, etc). Any disrespectful comments will not be tolerated
• Do not speak until you are called on-I will delegate the debate
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How it works• Disagree goes first-3 minutes to explain why you
disagree• Agree-3 minutes to explain why you agree• Both groups will discuss flaws and/or
inconsistencies and prepare for rebuttal (3 min)• Rebuttal:
– Agree first (5 min): what inconsistencies did you find on the other team
– Disagree (5 min): what inconsistencies did you find on the other team
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How it works• After rebuttal you can decide if you would like to
switch teams. Be prepared to explain why you switched teams.
• Discussion with groups in preparation for final thoughts
• Final thoughts:– Disagree (5 min): Main reason(s) why you disagree with
cloning– Agree (5 min): Main reason(s) why you agree with
cloning
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Gene Therapy discussionGuidelines:1. You cannot talk unless you are holding the ball.2. Your comments/statements must be regarding the
scientific information presented.3. Disrespect will not be tolerated. Bring an open
mind to the discussion but know that no one is asking you to change your opinion or agree with someone else’s opinion.
4. Everyone must speak once (this is how you receive a grade). It must be more than “yes, I agree”
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Write a paragraph (5-7 sentences)Answer the following questions in your paragraph:1. Do you agree or disagree with gene therapy? Why or
why not?2. Do you agree or disagree with gene enhancement?
Why or why not?3. If you make a choice to be tested for a particular
genetic disorder should a company (your job, insurance, etc) be able to make a choice to drop you based off the results? Why or why not?
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Warm Up 4/11
1. What was the purpose of the Human Genome Project?
2. Give one genetic disorder that scientists have attempted to correct by gene therapy.
3. What is the difference between reproductive cloning and therapeutic cloning?
4. Is colorblindness an autosomal disorder or sex-linked disorder?
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Warm Up
1. If you clone an organism, do you need a sex cell or a body cell from the organism you would like to clone?
2. What was the first cloned mammal?3. Explain the difference between reproductive
cloning and therapeutic cloning.
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Human Genome Project
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Purpose: To sequence base pairs in human DNA
Human Genome Project• Started in 1990 completed in
2003
• Research effort to map out all 20,000-25,000 genes on our 46 chromosomes in our DNA
• Over 3.3 billion nucleotides
• Conducted by scientists around the world 36
Benefits of Human Genome Project
• Improvements in medical prevention of disease, gene therapies, diagnosis techniques …
• Production of protein products for use in medicine, agriculture, bioremediation and pharmaceutical industries.
• Improved bioinformatics – using computers to help in DNA sequencing …
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More on gene therapy
The Human Genome Project is useful in determining whether individuals may carry genes for genetic conditions and in developing gene therapy.
Gene therapy is: the insertion of genes into an individual's cells and tissues to
treat a disease (hereditary diseases in particular) typically aims to supplement a defective mutant allele with a
functional one.
Gene therapy The process:1. Create a plasmid and insert it into a vector
plasmid– an engineered piece of DNA vector – vessel for a plasmid (ex. Viruses, bacteria, or fat capsules)
2. Insert the vector into human cells so it can multiply3. Insert human cells into person with a disorder
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Gene Therapy trials
• Cystic Fibrosis – remember it’s an autosomal recessive trait
• Since 1993, biologists have been using viruses as vectors to reduce symptoms of CF
Gene Therapy trials• Severe Combined Immunodeficiency – also
autosomal recessive• - impairs your T and B Cells of your immune system
– makes you an easy target for getting diseases• GT began in 1990 – researches extrated DNA from
patients, corrected it and reinserted. • Was successful EXCEPT some patients developed leukemia
Warm Up
1. What is a transgenic organism?2. What is a clone?3. Give one way in which biotechnology has
benefitted society/the environment.
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Benefits of Genetic Engineering
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Biotechnology -Biotechnology -
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• The use of gene science to create new products from plants and animals
• The use of gene science to create new products from plants and animals
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Biotechnology Provides:Biotechnology Provides:
• Improved food products
• Medical advances
• An enhanced environment
• Improved food products
• Medical advances
• An enhanced environment
Biotechnology BreakthroughsBiotechnology Breakthroughs• Insulin (1982)
– First commercial biotech product– Reliable, inexpensive source of
insulin
• Rice– Enriched with beta-carotene and iron
• Bananas– Containing edible hepatitis vaccine
• Insulin (1982)– First commercial biotech product– Reliable, inexpensive source of
insulin
• Rice– Enriched with beta-carotene and iron
• Bananas– Containing edible hepatitis vaccine
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Biotechnology BreakthroughsBiotechnology Breakthroughs
• Potatoes with higher solid content
• Garlic that lowers cholesterol
• Fruits and vegetables that reduce risks of cancer and heart disease
• Potatoes with higher solid content
• Garlic that lowers cholesterol
• Fruits and vegetables that reduce risks of cancer and heart disease
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Environmental BenefitsEnvironmental Benefits
• Reduced pesticide use
• Lower energy requirements
• Cleaner water
• Less soil erosion
• Reduced pesticide use
• Lower energy requirements
• Cleaner water
• Less soil erosion
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Plasmids• Circular DNA molecule • Found naturally in some
bacteria and are useful for DNA transfer
• They are able to pass readily from one cell to another, even when the cells are clearly from different species
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Why use bacteria?
Bacteria are used because they are:1. Small2. Reproduce quickly 3. They are living
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Example: Making Insulin for Medical Purposes
1. Plasmid is cut or cleaved by a restriction enzyme and human DNA is inserted.
2. The ring now has human DNA and is entered into another organism (such as a bacterial cell)
3. Now the bacteria can divide rapidly and produce many millions of cloned cells with the same human gene (so we get insulin that we can use to treat diabetes
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Plasmid Lab Directions
Work in pairs:1 person cuts out the DNA and tapes it together
(MUST BE IN ORDER AND IS ONE LONG STRIP)1 person cuts out the plasmid and tapes it
together (in a circle). This person also cuts out the enzyme cards
WAIT FOR ME ONCE THIS IS DONE!!!
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Plasmid Lab Directions1. Enzyme cards: find the one(s) that cut the bacteria
plasmid ONCE and do not cut off/cut through the GREY area (the bacteria replication site) at all.
2. Out of these selected enzyme cards apply them to your human DNA strip. Find the enzyme that cuts the DNA TWO TIMES. Once ABOVE the GREY area (the insulin gene) and once BELOW the GREY area.
3. DO NOT CUT YOUR STRIPS UNTIL YOU ARE SURE YOU HAVE THE CORRECT ENZYME TO USE. ASK ME IF YOU ARE UNSURE.
4. Answer discussion questions (one per person) 55
Warm Up
1. What is a plasmid?2. What is one reason why we use bacterial
plasmids to create insulin?3. What type of organic molecule is a restriction
enzyme?4. What is the function of a restriction enzyme?
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Warm Up
1. What is bioethics?2. Give one example of a job in the field of
bioethics.3. What is your opinion on patenting genes?4. What is your opinion on gene therapy? Gene
enhancement?
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Transgenic Organisms (Genetically Modified Organisms)
Organisms that have DNA from multiple species Uses: • Larger salmon = more food• Leaner meats = healthier• Drought or Frost resistant crops = hardier food for changing
climates good for farmers and consumers• Herbicide resistant crops = less soil and water contamination• Vitamin-rich crops = healthier diets
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How are organisms genetically modified?
1. In lab, fertilize egg with sperm of the same species.
2. Insert desired gene into the fertilized egg.
3. Return egg to female’s uterus for development.
Transgenic- genetically modified organism - source of new genetic material is from a different species.What is this?
It is a tobacco plant the has been transgenetically altered with the glowing genes of fire flies.
Useful Transgenic Organisms• Using mice to produce human ear• Using rice to produce proteins for human diet• Using bacteria to produce human proteins• Using cows to produce milk with human proteins• Using mice to inflict with human cancer and then cure it
http://www.mnn.com/green-tech/research-innovations/photos/12-bizarre-examples-of-genetic-engineering
Create your own GMO• Draw and color a picture of a genetically
modified organism that doesn’t exist yet
• On the back (In paragraph form!!!):1. Give me an explanation of the organism (What is it?) 2. How was it created (What genes did you add to it?) 3. Why did you choose to add the genes you added?4. What is this organisms purpose? (it must have one!)
How will it benefit society?
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Genetic Modification RAFT Writing
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ROLE AUDIENCE FORMAT TOPIC
Disgusted consumer Food and Drug Administration (FDA)
Letter GMOs in grocery stores or restaurants
Biotechnology scientist
Food and Drug Administration (FDA)
Letter A new GM Food that you would like to put on the market
Biotechnology scientist
Cancer Centers of America
Letter A new transgenic organism that proves to have an 85% success rate at curing cancer.
Disgusted PETA member
Biotechnology scientist
Letter The unethical treatment of animals in an attempt to find the cure for cancer
Warm Up 4/15
1. What is a transgenic organism?2. What is a clone?3. Give one way in which biotechnology has
benefitted society/the environment.
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Warm Up
1. What is a plasmid?2. What is one reason why we use bacterial
plasmids to create insulin?3. What type of organic molecule is a restriction
enzyme? (carb, lipid, protein, nucleic acid)4. What is the function of a restriction enzyme?
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Stem Cells
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Specialized and Unspecialized Cells
• Specialized cells know their job – they can only become that type of cell(heart cell reproduces and makes more heart cells)
• Unspecialized cells do not have a job yet – they can become any type of cell in the body
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Stem Cells (not in notes)• “Blank” cells – immature cells that have not
formed into a specific type of cell yet• Can be used to turn into any type of cell
– Ex. Make a new liver for someone
Stem cells Specialized Cells (not in notes)
• Remember “adult” cells take different forms based on their functions
Nerve Cell
Blood Cell
Xylem /Phloem Cell
Sperm/Egg Cell
Muscle Cell
Stem Cells• Stem cells can grow into many different types of cells in
the body during early life and growth
• Serve as an internal repair system, dividing without limit to replenish other cells as long as the organism is alive
• When a stem cell divides, each new cell has the potential to stay a stem cell or become another type of cell (like a muscle, blood, or brain cell)
• This all makes stem cells ideal to use for making other types of cells for medical purposes
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The controversy: obtaining stem cells
2 Types of stem cells:1.) Embryonic: from a fertilized egg2.) Somatic/Adult: from adult non-sex cells
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Not in notes• Embryonic: can become all cell types of
the body
• Adult stem cells: are thought to be limited to differentiating into different cell types of their tissue of origin.
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Not in notes• Embryonic: can be grown relatively easily
in culture
• Adult stem cells: rare in mature tissues, so isolating these cells from an adult tissue is challenging– This is an important distinction, as large
numbers of cells are needed for stem cell replacement therapies.
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2 types of Stem Cells (not in notes)Embryonic Stem Cells
• Can develop into almost every type of human cell (greater chance for differentiation)
• Divide into new cells quickly and for an unlimited time
• Grow easily in a lab• Can have problems donating to
someone else’s immune system• Less mutations in cells• Easy to harvest – just destroy an
embryo ethical controversies
Adult Stem CellsCan only develop into some
types of human cells (less chance for differentiation)
- Divide into new cells more slowly
- Do not grow easily outside of human tissue
- Patient usually receives his/her own cells – no immune complication
- Potential for more mutations in the cells
- Hard to harvest (in bone marrow
Conclusion: it is easier to use embryonic stem cells than adult stem cells for medical purposes. But is it ethical?
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Warm Up
1. What are the 2 types of stem cells?2. Which type of stem cell is controversial?3. Which type of stem cell can be transferred easily
with no risk of rejection of the transplant?4. Which type of stem cell is formed by fertilization of
an egg cell?5. Which type of stem cell comes from bone marrow?
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