Chapter 9

Question 0

What are some applications for genetic engineering?

Answer 0

• to produce medically/commercially valuable proteins
• to produce specific DNA sequences
• as a tool for studying gene function and regulation

Question 1

What is genetic engineering?

Answer 1

the deliberate modification of the characteristics of an organism by manipulating its genetic material.

Question 2

What is a restriction enzyme?

Answer 2

Enzyme that cuts DNA molecule at a specific spot

Question 3

How is a restriction typically Palindromic?

Answer 3

They cut both strands of DNA at the “same” site so they will have the same sequence only in different directions

Question 4

What way does DNA move on gel electrophoresis?

Answer 4

Migrates towards (+)

Question 5

What are a few uses for genetically engineered bacteria?

Answer 5

• treating anemia, dwarfism, diabetus
• making cheese
• making pharmaceuticals

Question 6

Why would we want to cut the DNA of interest and the plasmid (vector) with the same restriction enzyme?

Answer 6

So they are complimentary

Question 7

What is a reporter gene?

Answer 7

• gene that researchers attach to a sequence of another gene of interest in order to track it
• Similar to a selective gene

Ex. Green fluorescent protein

Question 8

What are the functions of a DNA library?

Answer 8

• isolates genomes

- inserts fragments into vectors

Question 9

DNA genes of interest are introduced to host cell through ________.

Answer 9

Transformation

Question 10

What is a selectable marker?

Answer 10

A gene that allows cells to grow in otherwise inhibitory conditions

Ex. Cells that take up ampicillin marker can resist the antibiotic and grow on the media

Question 11

What is a second marker used for?

Answer 11

To distinguish between cells that contain the recombinant plasmid and those that don’t

Ex. Intact vector- grows blue
Recombinant molecule- white

Question 12

What is the role of DNA ligase in forming a recombinant molecule?

Answer 12

After the “sticky ends” of the gene of interest come in contact with the restriction site on a cell the enzyme covalently closes the plasmid(vector).

Question 13

What effect does the spliced gene of interest have on the host cell?

Answer 13

Interrupts normal process & the cell no longer functions properly

Question 14

What happens before the plasmid (vector) & DNA of interest can be introduced into the host cell?

Answer 14

They must be cut with the same restriction enzyme & joined together as a recombinant molecule.

Question 15

Why is the second marker important for selecting for recombinant molecules?

Answer 15

• not all cells receive the gene of interest.
• some close without taking in any DNA.
• some covalently close around regular DNA

Question 16

How can you visualize PCR?

Answer 16

Gel electrophoresis

Question 17

What are the 3 steps to the amplification cycle?

Answer 17

1. Heat to 95 to denature DNA
2. Lover temp to 50 for primers to adhere
3. Reheat to 72 so DNA synthesis can occur

Question 18

What defines the length of PCR?

Answer 18

Primers

They get shorter each cycle

Question 19

What is the function of a DNA probe?

Answer 19

To locate specific nucleotide sequences

Question 20

What is a DNA probe composed of?

Answer 20

Single-stranded piece of DNA

Question 21

What is the purpose for colony blotting?

Answer 21

To identify which clonies contain a specific sequence of interest

Question 22

What are the 5 steps in colony blotting?

Answer 22

1. Colonies begin on agar plate
2. Colonies are transferred to nylon membrane
3. Soak membrane in alkaline solution to lyse cells & denature DNA
4. Add probe to bind to the DNA of interest
5. Probe reveals the colonies with probe of interest

Question 23

If the new DNA is inserted within the host cell, the second marker is

Answer 23

Inactivated