What is true about the steps of PCR shown in the diagram given below?

l. Step A occurs at the temperature of 95-98${}^{\mathrm{o}}$ C

ll. Step B occurs at the temperature of 55${}^{\mathrm{o}}$ C

lll. Step C occurs at the temperature of 72${}^{\mathrm{o}}$ C

1. l and ll only

2. l and lll only

3. ll and lll only

4. l, ll and lll

A and B in the pBR 322, shown in the diagram given below, respectively represent recognition sequences of :

1. BamH I and Sma I

2. Hind II and Sma I

3. BamH I and SaI I

4. SaI I and Hind II

What is true A,B and C in the given diagrammatic representation of rDNA technology ?

I. At A same restriction enzyme is used to cut both foreign and vector DNA

II. The enzyme used at B is DNA ligase

III. Step C can be called as transformation

1. I and II only

2. I and III only

3. II and III only

4. I,II and III

The process of separation and purification of expressed protein before marketing is called

(1) upstream processing

(2) downstream processing

(3) bioprocessing

(4) postproduction processing

What is the criterion for DNA fragments movement on agarose gel during gel electrophoresis ?

(1) The larger the fragment size, the farther it moves

(2) The smaller the fragment size, the farther it moves

(3) Positively charged fragments move to farther end

(4) Negatively charged fragments do not move

A gene, whose expression helps to identify transformed cells is known as

1. selectable marker                 

2. vector

3. plasmid                                 

4. structural gene

The DNA fragments separated on an agarose gel can be visualised after staining with

(1) bromophenol blue

(2) acetocarmine

(3) aniline blue 

(4) ethidium bromide

Stirred-tank bioreactors have been designed for:

(1) purification of product

(2) addition of preservatives to the product

(3) availability of oxygen throughout the process

(4) ensuring anaerobic conditions in the culture vessel

A foreign DNA and plasmid cut by the same restriction endonuclease can be joined to form a recombinant plasmid using

(1) Eco RI                       

(2) taq polymerase

(3) polymerase III           

(4) ligase

Which of the following is not a component of downstream processing?

1. Separation

2. Purification

3. Preservation

4. Expression