Topic 2

Question 1

Step 1

Answer 1

• collecting the sample
• can be just about anything
• storing samples can have a big impact on its ability to extract the proper amount of DNA

Question 2

sample storage

Answer 2

• fresh if possible
• freeze quickly
• use methods of flash freezing

Question 3

flash freezing

Answer 3

• liquid nitrogen or dry ice
• avoiding ice crystals as they can damage the sample/DNA
• if in the field, can use products such as DNA/RNA shield which will lyse cells and inactivate the nucleases

Question 4

lyse

Answer 4

• methods that are used to destabilize the membranes of cells to break them down into smaller fragments

Question 5

lysate

Answer 5

• what you end up with after you lyse your cells
• the liquid containing components of lysed cells

Question 6

single cell extraction

Answer 6

-usually have to start with a whole genome amplification in order to have enough genes to sequence
- chemical lysis technique tend to be the least harsh on cell membrane

Question 7

plasmids

Answer 7

• small, supercoiled, circular DNA molecules
• mostly found in prokaryotes

Question 8

gel filtration chromatography

Answer 8

• seperate based on size
• large will elute first

Question 9

ion-exchange chromatography

Answer 9

• separate based on charge
• oppositely charged beads will elute first

Question 10

SDS PAGE

Answer 10

• separates proteins based on molecular weight
• SDS makes all the proteins have the same charge so they go in the same direction due to the electrical feild

Question 11

2D PAGE

Answer 11

• separates proteins based on isoelectric point
• then based on molecular weight
• allows researchers to detect members of a gene families
• to detect a spot for each polypeptide loaded