1. A nicked RNA molecule can be ligated by

A. T4 RNA ligase

B. DNA polymerase

C. T4 DNA ligase

D. all of these

Answer: C



2. The tertiary structure of yeast tRNA

A. involves extensive base stacking interactions

B. resembles the 3-dimensional structure of other tRNAs

C. is maintained mostly by non-Watson-Crick base pairing

D. all of the above

Answer: D


3. Which of following RNA characteristically contains unusual purines and pyrimidmes?





Answer: D


4. The anticodon is a structure on

A. mRNA.

B. tRNA.

C. aribosome.

D. rRNA.

Answer: B


5. The genetic material of retroviruses such as HIV is



C. protein

D. all of these

Answer: B


6. Retroviruses replicate via __________ intermediate





Answer: B


7. During RNA synthesis, the DNA template sequence 5’Tp Ap Gp Cp 3' Would be transcribed to produce which of the following RNA sequence?

A. 5'-Ap Tp Cp Gp-3'

B. 5'-Gp Cp Up Ap-3'

C. 5'-Gp Cp Tp Ap-3'

D. 5'-Ap Up Cp Gp-3'

Answer: B


8. RNA instability in alkaline solutions is due to

A. adenine

B. ribose

C. uracil

D. single strand nature

Answer: B


9. In RNA, uracil pairs with

A. adenine

B. cytosine

C. thymine

D. guanine

Answer: A


10. Two features of the tRNA molecule associated, in converting the triplet codon to an amino acid, are

A. in the T Loop and D stem and loop

B. in the anticodon loop and D stem loop

C. in the anticodon loop and the 3' CCA end

D. none of the above

Answer: C


11. Which of the following is the smallest of the RNAs?

A. Messenger RNA

B. Transfer RNAs

C. Ribosomal RNAs

D. All of these

Answer: B


12. The mRNA from which of the following would contain a poly-A tail?

A. A restriction endonuclease from E. coli

B. Bacterial alpha-amylase

C. Human insulin

D. Bacteriophage DNA ligase

Answer: C


13. What is the average size (in bp) of a mature t-RNA?

A. 80 bp

B. 100 bp

C. 120 bp

D. 140 bp

Answer: A


14. What modified base is at the 5' extremity of a capped eukaryotic m-RNA?

A. 1-methyl-adenosine

B. 2'-O-methyl-guanosine

C. 7-methyl-guanosine

D. 1-methyl-guanosine

Answer: C


15. What is the function of messenger RNA?

A. It carries amino acids

B. It is a component of the ribosomes

C. It is a direct copy of a gene

D. It is the genetic material of some organisms

Answer: C