Recombinant DNA

Question 1

a DNA that has

an Exogenous DNA or Gene attached with a vector DNA

Answer 1

R-DNA

Question 2

1. Polymerase Chain Reaction (PCR) 2. DNA Sequencing

Answer 2

R-DNA techniques

Question 3

What is cDNA?

Answer 3

A newly synthesized DNA which is complementary to the template, is called as ‘cDNA’

Question 4

Polymerase chain reaction (PCR)

Answer 4

1. DNA synthesis done repeatedly for multiple times

2. Amplify a target DNA in large amount

Question 5

Why we need PCR?

Answer 5

1. Super fast and super sensitive technique
2. Any region of a target DNA can be selected
3. Amount of target DNA is increased/amplified

Question 6

Requirements for PCR?

Answer 6

1. Template DNA
2. Two primers: targeting both strands small single-stranded DNA molecules
3. Substrate: dNTP (dATP, dCTP, dGTP, dTTP)
4. Enzyme Taq DNA polymerase

Question 7

Template is not visible

Answer 7

Because very little amount

Question 8

PCR steps

Answer 8

1- denaturation 94*C

2-annealing

3- extension 74*C

Question 9

Anealing depends on

Answer 9

The primer size

Question 10

Annealing temperature is selected based on the

Answer 10

melting temperature (Tm) of a primer

Question 11

Melting temperature

Answer 11

Tm = 2 (Number of A and T) + 4 (Number of C&G) oC

Question 12

Annealing temperature must be

Answer 12

5o C less than the Tm

Question 13

Requirements for DNA sequencing (Sanger’s )

Answer 13

DNA / gene

Primer complementary to only one strand

Substrate dNTP (dCTP, dGTP, dTTP, dATP)

Terminators ddNTP (ddCTP, ddGTP, ddTTP, ddATP) Taq DNA polymerase

Question 14

DNA sequencing is accomplished in two steps

Answer 14

1. Sequencing reaction to generate sequence
   Base selective termination of DNA synthesis
2. Electrophoresis to obtain sequence
   Separation of terminated fragments by capillary electrophoresis

Question 15

Therefore amplification is not a geometric progression?

Answer 15

The product in this case does not act as template in the next cycle