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

Which of the following restriction enzymes produces blunt ends?

1. Sal I                           
2. Eco RV
3. Xho                           
4. Hind III

Which of the following is a endonuclease?

(1) Protease

(2) DNase I

(3) RNase restriction

(4) Hind II

The Taq polymerase enzyme is obtained from

1. Thiobacillus ferroxidans

2. Bacillus subtilis

3. Pseudomonas subtilis

4. Thermus aquaticus

The cutting of DNA at specific locations became possible with the discovery of 

(1) restriction enzymes

(2) probes

(3) selectable markets

(4) ligases

The DNA molecule to which the gene of interest is integrated for cloning is called: