cDNA probes are copied from the messenger RNA molecules with the help of

1. restriction enzymes

2. reverse transcriptase

3. DNA polymerase

4. adenosine deaminase.

Hirudin is

(1) a protein produced by Hordeum vulgare, which is rich in lysine

(2) a toxic molecule isolated from Gossypium hirsutum, which reduces human fertility 

(3) a protein produced from transgenic Brassica napus, which prevents blood clotting

(4) an antibiotic produced by a genetically enginnered bacterium, Escherichia coli 

Recombinant DNA technology involves several steps in which initial step is of isolation of the DNA. Which enzymes are used in the process for the breakdown of fungal cell, plant cell and bacterial cell respectively?

(1) Lysozyme, lipases, trypsin

(2) Chitinase, cellulase, lysozyme

(3) Chitinase, cellulase, trypsin

(4) Trypsin, lipases, cellulase

What is the source of EcoRI?

(1) Escherichia coli R 1

(2) Escherichia coli R I 13

(3) Escherichia coli R Y 13

(4) Escherichia coli R X 13

Which of the following is a cloning vector?

(1) DNA of Salmonella typhimurium

(2) Ti plasmid

(3) Amp' and Tet' loci

(4) Ori minus PBR322

Which of the following is a palindromic sequence?

(1) 5'-CGTATG-3'           

      3'-CGAATG-5'

(2) 5'-CGAATG-3'

     3'-GCATAC-5'                 

(3) 5'-GAATTC-3'

     3'-CTTAAG-5'      

(4) 5'-GACTAC-3'

     3'-CTTAAG-5'      

How are transformants selected from nontransformants?

1. Presence of more than one recognition site in the vector DNA.

2. Presence of alien DNA into the vector DNA results into insertional inactivation of selectable marker.

3. Antibiotic resistance gene gets inactivated due to insertion of alien DNA.

4. Both 2 and 3.

Which of the following is not a characteristic of pBR322 vector? 

(1) It is the first artificial cloning vector constructed in 1977 by Boliver and Rodriguez.

(2) It is the most widely used, versatile and easily manipulated vector.

(3) It has two antibiotic resistance genes, tet^R and amp^R.

(4) It does not have restriction site for Sal I.

Select the correct order of processing of PCR.

(1) Extension, primer annealing, denaturation

(2) Denaturation, primer annealing, extension

(3) Denaturation, extension, primer annealing

(4) Primer annealing, denaturation, extension

Plasmid vector in DNA recombinant technology means

1. a virus that transfers gene to bacteria

2. extra-chromosomal autonomously replicating circular DNA

3. sticky end of DNA

4. any fragment of DNA carrying desirable gene