Quick revision: every question with its correct answer. For the full explanation, open the test and tap View Solution.
8.4 Replication, Transcription & the Genetic Code — Test 2
Q1. In the DNA double helix, the bases pair as:✓ A-T and G-C
Q2. DNA replication is best described as:✓ Semiconservative
Q3. Which of the following is a step in DNA replication?✓ All of these
Q4. The leading strand at a replication fork is synthesised:✓ Continuously toward the fork
Q5. In bacteria, the RNA primers laid down during replication are removed by:✓ DNA polymerase I
Q6. Of the 64 codons, the number that specify amino acids (sense codons) is:✓ 61
Q7. The codon that serves as the initiation (start) codon is:✓ AUG
Q8. The pairing between a codon on mRNA and the anticodon on tRNA during translation is part of:✓ Decoding (reading the message)
Q9. In Nirenberg's in-vitro experiments, a synthetic RNA of repeating cytosines (poly-C) directed the synthesis of a polypeptide of:✓ Proline
Q10. The main components of ribosomes are:✓ Ribosomal RNA (rRNA) and proteins
Q11. In bacteria, the Shine-Dalgarno sequence of mRNA base-pairs with the:✓ 16S rRNA (anti-Shine-Dalgarno)
Q12. In the lac operon, when both lactose and glucose are very low, the binding status of regulatory proteins is:✓ Both the repressor and CAP-cAMP are bound to their sites
Q13. Rho-independent (intrinsic) transcription termination in bacteria relies on:✓ A GC-rich RNA hairpin followed by a poly-U stretch (no protein factor)
Q14. During transcription, DNA gyrase helps by:✓ Introducing negative supercoils to relieve torsional strain
Q15. Protein splicing refers to the removal of:✓ An internal protein segment (intein), joining the flanking exteins
Q16. Which statement about the human mitochondrial genome is correct?✓ It has essentially no introns
Q17. The human mitochondrial genome contains a total of how many genes?✓ 37
Q18. The G+C content of a double-stranded DNA is 68%. The expected G+C content of an mRNA transcribed from it is approximately:✓ About 68%
Q19. LINEs (long interspersed elements) and SINEs (short interspersed elements) in the human genome are types of:✓ Mobile genetic elements (transposable elements)
Q20. Match each molecular feature with its description and select the correct option.✓ A-iii, B-iv, C-i, D-ii