L16- 18: Cloning and Hydribisation

Question 1

define recombinant dna

Answer 1

molecule of dna that has originated from 2 or more dna fragments

Question 2

define cloning

Answer 2

production of identical copies of partiliar dna molecule

Question 3

what do restriction enzyme sdo

Answer 3

cut dna at specific sites
leaving 3’ hydroxyl and 5’ phosphate groups
-can be blunt or sticky ends

Question 4

function of restriction enzymes

Answer 4

protect cells from invaders

act together with methylase

Question 5

what does dna ligase do to annealed dna

Answer 5

fill in cap of sugar phosphate bonds

covalently link

Question 6

what is a plasmid

Answer 6

circular dna molecule

Question 7

how do you make bacterial cells permeable to dna

Answer 7

heat shock or electroporation

Question 8

process of electrophoresis

Answer 8

dna carries negative charge and migrates to pos electrodes

Question 9

why are plasmid vectors used in cloning

Answer 9

• moved from cell to cell easily.
• contain the genes that control their own replication.
• no detrimental effects on their host cells.

Question 10

what does hydrbidiation occur between

Answer 10

2 dna
2 RNA > double stranded rna
dna + rna= hybrid

Question 11

3 techniques for nucleic acid hybridisation

Answer 11

southern/northern blotting

in situ hybridisation

Question 12

3 steps of PCR

Answer 12

denaturing
annealing
extending

Question 13

explain pcr

Answer 13

• temp increase= unwinds + separated
  temp decrease= primers attach to complementary
  primers annealed + taq polymerase copies dna from primer and adds nucleotides
  temp increas= strand seperated