In 1953, James Watson and F. Crick proposed the Double Helix model of DNA and got Nobel Prize. Their model of DNA was based on:
A. X-ray diffraction of DNA produced by M. Wilkins and R. Franklin
B. Griffith’s experiment.
C. Hershey - Chase experiment
D. Chargaff’s rule of base equivalence (A + G / T + C = 1)

(1) A, D             
(2) A, B, C, D           
(3) B, C, D             
(4) A, B, C

In one polynucleotide chain of a DNA molecule the ratio of A + T / G + C is 0.3. What is the A + G / T + C ratio of the entire DNA molecule:

(1) 0.3                 

(2) 0.6                 

(3) 1.2                 

(4) 1

DNA polymerase:
A. Is the main enzyme for RNA synthesis
B. Is DNA dependent DNA polymerizing enzyme
C. Is a highly efficient enzyme
D. Is catalyzes a reaction with a high degree of accuracy
(1) C, D             

(2) A, B, C, D               

(3) B, C, D             

(4) A, B, C

The difference(s) between mRNA and tRNA is / are that:
A. mRNA has more elaborated 3-dimensional structure due to extensive base-pairing.
B. tRNA has more elaborated 3-dimensional structure due to extensive pairing.
C. tRNA is usually smaller than mRNA.
D. mRNA bears anticodon but tRNA has codons.
(1) A, C                   

(2) A, B, C, D                 

(3) B, C                   

(4) A, B, C

In eukaryotes the gene expression is regulated at:
A. Transcriptional level
B. Processing level
C. Transport of mRNA from nucleus to the cytoplasm
D. Translational level
(1) A, C               

(2) A, B, C, D                 

(3) B, C, D                     

(4) A, B, C

In prokaryotes, gene regulation occurs at the level of:

(1) Transcription                               

(2) Translation

(3) Post transcription                         

(4) Post translation

Characteristic(s) of most DNA is / are:
A. A pairs with T by 2 hydrogen bonds.
B. Antipolarity of complementary chains
C. 20Aº diameter
D. 10 bps/turn 
(1) A, C                 

(2) A, B, C, D                     

(3) B, C, D                 

(4) A, B, C

A. DNA polymorphism plays important role in evolution and speciation.
B. 99.9% nucleotides bases are exactly same in all people
C. Chromosome 1 has the fewest genes (23) and Y-chromosomes has most genes (2968)
D. BAC and YAC have been used in Human Genome Project.
(1) All correct                   

(2) All incorrect

(3) A, B, D are correct       

(4) B, C, D are correct

Which one(s) is / are correct?
A. In prokaryotes, a single type of RNA polymerase can transcribe mRNA, tRNA and rRNA.
B. In eukaryotes, RNA polymerase I transcribes rRNAs (28S, 18S, and 5.8S), whereas RNA polymerase III is responsible for the transcription of tRNA, 5srRNA, and snRNAs.
C. RNA pol II transcribes hnRNA in eukaryotes.
D. Ribosomal large subunit has p and A-sites.
(1) A, C               

(2) A, B, C, D                 

(3) B, C, D                 

(4) A, B, D

Go through the following diagram of Nucleosome (structural unit of chromatin). Identify its componential parts indicated by A, B and C: