Biotechnology

Question 1

What is recombinant DNA?

Answer 1

DNA that is substituted from another strand of DNA into another

Question 2

How can scientists use plasmids and bacteria to clone (make many identical copies of) a specific gene?

Answer 2

• When a gene in a plasmid in bacteria is changed, bacteria can make multiple copies of that gene fast, since bacteria have short lifespans
• Scientists take these plasmids and use enzymes to cut them apart so they can get a specific part of the plasmid

Question 3

Why might biologists want to clone a gene? Of what use is this technology/technique? How could you get a gene from one organism into another?

Answer 3

• Say there is a desirable gene that one animal has but the other doesn’t, and it would be beneficial for that animal to have it
• Example (Cloning GFP from Jellyfish and moving it to other animals), or like moving the tastier apple gene to other apples
• You would first get a DNA sample, copy it with DNA Polymerase and other necessary enzymes, then by manipulating restriction enzymes, cut out the gene that you want
• Then you can copy that cut out gene
• A gene can be cloned so gel electrophoresis can be performed better

Question 4

How is DNA technology useful in producing therapeutic hormones?

Answer 4

• You can take a gene out of the cell that creates the hormone and put it into a cell that doesn’t already make that hormone

Question 5

How is DNA technology useful in diagnosing and treating disease?

Answer 5

You can clone a gene that deals with bacteria and put it into a vaccine

Question 6

How is DNA technology useful in developing vaccines?

Answer 6

You can clone a gene that deals with bacteria and put it into a vaccine

Question 7

How is DNA technology useful in developing genetically modified (GMO) crops & livestock?

Answer 7

You can make crops and livestock more tasty, more fatty, more resistant to some virus/diseases, perhaps you could make some crops more durable and resistant… a lot of possibilities

Question 8

When designing a plasmid with a gene of interest, what types of enzymes do biologists use to cut DNA at specific sequences?

Answer 8

Restriction enzymes

Question 9

Where do restriction enzymes come from? Why might one enzyme be used versus another? How do they work?

Answer 9

Come from bacterial cells to chop up foreign DNA, each one cuts at different restriction sites

Question 10

What is a restriction site and why are they palindromes?

Answer 10

• They are where restriction enzymes recognize certain patterns
• They are palindromes so they can be read in the 5-3 direction on either strand and be the same

Question 11

What enzyme can biologists use to “paste” together DNA?

Answer 11

Ligase

Question 12

How do you use a micropipette? (first and second stop, changing tips, etc)

Answer 12

• When you hold a micropipette you put your thumb over the top of it, where there is a plunger and another button (which releases the tip)
• The plunger has two stops, the first one extrudes all of the liquid from the tip, and the second stop shoots a burst of air through the tip which pushes the drop of liquid off of the end of the tip

Question 13

How do you prevent cross-contamination when micropipetting small amounts of liquid?

Answer 13

You switch the tips in between using the micropipette to pipette liquids

Question 14

What is gel electrophoresis and what is this technique used for? How does it work?

Answer 14

• After micropipetting the solution into the wells of a gel slab, you turn something on that makes electricity flow through the gel (positive and negative charges coming from separate directions)
• One side of the container the gel is in has a positive charge, and the other is negatively charged, so the DNA will slowly move toward the positive end of the container (bigger pieces move less)

Question 15

How do you set up a gel electrophoresis experiment to get viable results?

What are the required components needed to analyze your results? (ex: control DNA, DNA ladder, loading dye, semilog graph paper) What is an appropriate control when running a restriction digest on a gel?

Answer 15

-You need DNA ladder, DNA, dye, agarose gel, a brine solution, electricity and two diodes, and a UV light

Question 16

How do you construct a plasmid map, given RE digest results?

Answer 16

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Question 17

Can you predict gel electrophoresis results (band pattern) of a RE digest, given a map of the DNA being tested?

Answer 17

The shortest strands would travel the farthest

Question 18

What is a SNP? How are they useful in DNA fingerprinting?

Answer 18

• Single nucleotide polymorphism (variation)

Question 19

What is a RFLP? How are they useful in DNA fingerprinting?

Answer 19

• The DNA sequence at a specific place may exhibit small differences
• May alter a restriction site
• Such alterations change the lengths of the restriction fragments formed by that enzyme when it cuts DNA
• Serve as genetic markers for particular loci in the genome

Question 20

How could a SNP cause a RFLP?

Answer 20

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Question 21

How do you ‘read’ a gel to determine the size of the DNA pieces in each lane?

Answer 21

-You compare your markings to the markings from a DNA ladder, or a piece of DNA with known size