Lab Final

Question 1

What primers were used in the GMO lab?

Answer 1

tubulin and 35S

Question 2

What is a 35S promoter? How many PCR primers are used to amplify this region?

Answer 2

35S promoter drives the expression of glyphosate-resistance, and one primer the 35S primer

Question 3

What is the purpose of identifying tubulin?

Answer 3

Tubulin is present in all plants. Identifying tubulin proves you were looking at a plant product.

Question 4

Why did we test Round-Up Ready soy and Wild Type soy products?

Answer 4

Round-Up Ready is genetically modified and wild type soy plants are not genetically modified. Those were the positive and negative controls.

Question 5

What was the length of the primers used? Why is this a good length?

Answer 5

The primers were about 25 letters long. This is a good length because it is less likely for the primer to bind to non-target DNA

Question 6

What stains could have been used on the gel?

Answer 6

carolinaBLU, CoomassieBlu, Ethydium Bromyde,

Question 7

Why is the Drosophila Melanogaster a good model organism?

Answer 7

easy to keep in lab, short generation time, easy to see inherited traits, 8 chromosomes

Question 8

Why are we looking at the chromosomes found in the salavary gland?

Answer 8

The chromosomes found in the salavary gland could be seen with a compound microscope after fixation

Question 9

What are polytene chromosomes?

Answer 9

over-sized chromosomes that have developed from normal chromosomes

Question 10

Why do the chromosomes have a banding pattern? What are the light and dark regions?

Answer 10

The banding pattern is visible landmarks to identify the location of a gene. The dark bands are whrer DNA is tightly packed (heterochromatin) and light bands are where it is less densely packed (euchromatin)

Question 11

Why is there a “puff” sometimes in the chromosomes?

Answer 11

The “puff” is where the DNA has unwound its self to make it accessible to translation machinery

Question 12

What in a drosophilia cell?

Answer 12

8 chromosomes, 4 pairs

Question 13

What is the purpose of CaCl?

Answer 13

CaCl is to

Question 14

What role does IPTG play in expressing GFP?

Answer 14

When the lac repressor binds to the promoter T7 polymerase is blocked & GFP cannot be expressed. When IPTG is added the lac repressor is inactivated and T7 is expressed.

Question 15

How is GFP used as a marker gene?

Answer 15

GFP is tagged to a specific gene and when the gene is expressed so is GFP

Question 16

What is the purpose of the heat shock?

Answer 16

The heat shock opens the pores in the bacterial cell wall so the vector can enter

Question 17

What would happen if cells weren’t placed on ice immediately after the heat shock?

Answer 17

It would be possible the vector could escape the cell because the cell wall would be open too long

Question 18

Why were plates incubated at 37C?

Answer 18

Plates were incubated to allow cell wall recovery and growth of the bacteria

Question 19

What was the purpose of all four bacterial plates?

Answer 19

-DNA on LB plate: +control, show the bacteria will grow
-DNA on AMP plate: -control, show it doesnt have AMPR
+DNA on +AMP: grow bacteria on AMP
+DNA on +AMP/+IPTG: grow bacteria, glowing colonies

Question 20

What can influence transformation efficiency?

Answer 20

recovery time, cross-contamination, shock wasn’t preformed quick enough

Question 21

Name 2 arguments for the use of genetically modified crops

Answer 21

1. crop yield

2. insect resistance

Question 22

Name 2 arguments against the use of genetically modified crops

Answer 22

1. unnatural

2. may cause super wees or kill off non target insects

Question 23

What compounds are needed for PCR

Answer 23

h20, taq, primers, buffer, mgcl2, dNTPs