In most prokaryotes the transcription unit is :

(1) Mono-cistronic

(2) Poly-cistronic

(3) Multi-cistronic

(4) Uni-cistronic

What defines the position and presence of coding and a template strand in the transcription unit ?

(1) Structural gene

(2) Ori

(3) Terminator

(4) Promoter

Which of the following is true for both transcription and DNA replication?

1. Principle of complementarity governs the processes

2. Only of the two strands act as template

3. Only a segment of both strands is involved 

4. Adenine base pairs with thymine

The DNA dependent DNA polymerases catalyze:

1. Only in 3'-5' direction

2. Only in 5'-3' direction

3. In both directions

4. In neither directions

Which of the following acts as the substrate and provide energy for DNA replication?

(1) Dideoxyribonucleoside triphosphates

(2) Ribonucleoside triphosphates

(3) Deoxyribonucleoside triphosphates

(4) Deoxyribonucleotide triphosphates

Which non-radioactive isotope was used by Meselson and Stahl to label DNA in their experiment?

\(1.\ {}^{35}S\)

\(2.\   {}^{15} N\)

\(3.{}^{32} P\)

\(4.\   N o n e\)

A molecule that can act as a genetic material must fulfill all the following criteria except :

(1) It should be able to generate its replica

(2) It should chemically and structurally be stable

(3) It should provide scope for rapid mutations

(4) It should be able to express itself in the form of "Mendelian Characters"

The unequivocal proof that DNA is the genetic material was provided by :

(1) Avery, Macleod and McCarty

(2) Hershey and Chase

(3) Meselson and Stahl

(4) Watson and Crick

Which of the following is not a feature of the double helix model of DNA ?

(1) The two chains have anti-parallel polarity

(2) A purine always comes opposite to a pyrimidine

(3) The pitch of the DNA is 3.4 nm

(4) The two chains are coiled in a left handed fashion

According to Erwin Chargaff, for a double stranded DNA

(1) The ratios between Adenine and Thymine, and, Guanine and Cytosine are constant and equals one. 

(2) The ratios between Adenine and Thymine, and, Guanine and Cytosine are constant but is not equal to one. 

(3) The ratios between Adenine and Guanine, and,Thymine, and Cytosine are constant and equals one. 

(4) The ratios between Adenine and Guanine, and, Thymine and, Cytosine are constant but is not equal to one.