This quiz works best with JavaScript enabled. Home > Class 12 > Class 12 Biology Chapter 6 Molecular Basis Of Inheritance – Quiz 41 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Biology Chapter 6 Molecular Basis Of Inheritance Quiz 41 (25 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. Which is the first step? A) DNA Helicase unwinds original DNA strand. B) RNA Primase lays down RNA primer for new nucleotide bases. C) DNA polymerase builds new strands by bring in new nucleotide bases. D) Ligase knits together fragments on lagging strandTagsDNA replication process. Show Answer Correct Answer: A) DNA Helicase unwinds original DNA strand. 2. Leading strand A) Replication is continuous on strand. B) Replication is discontinuous on strand. C) Small sections of DNA formed during discontinuous replication. D) None of the above. Show Answer Correct Answer: A) Replication is continuous on strand. 3. Pick the correct pair with respect to primers used in DNA replication. A) RNA primer-for both prokaryotes and eukaryotes. B) DNA primer-for both prokaryotes and eukaryotes. C) DNA primer-for eukaryotes only. D) RNA primer-for prokaryotes only. Show Answer Correct Answer: A) RNA primer-for both prokaryotes and eukaryotes. 4. THE EQUIVALENT OF STRUCTURAL GENE IS A) MUTON. B) CISTRON. C) OPERON. D) RECON. Show Answer Correct Answer: B) CISTRON. 5. Which RNA carries amino acids? A) MRNA. B) TRNA. C) SnRNA. D) HnRNA. Show Answer Correct Answer: B) TRNA. 6. Which is the fourth step? A) DNA Helicase unwinds original DNA strand. B) RNA Primase lays down RNA primer for new nucleotide bases. C) DNA polymerase builds new strands by bring in new nucleotide bases. D) Ligase knits together fragments on lagging strandTagsDNA replication process. Show Answer Correct Answer: D) Ligase knits together fragments on lagging strandTagsDNA replication process. 7. Which enzyme proofreads the DNA after replication to catch any mistakes? A) Primase. B) Proof-read-ase. C) DNA polymerase. D) Helicase. Show Answer Correct Answer: C) DNA polymerase. 8. In the template with polarity 3'-5' the replication is A) Continuous. B) Discontinuous. C) Sometimes continuous. D) Sometimes discontinuous. Show Answer Correct Answer: A) Continuous. 9. This enzyme helps helicase unzip DNA by relieving supercoiling A) Topoisomerase. B) Exonuclease. C) DNA Primase. D) DNA PolymeraseTagsDNA replication enzymes. Show Answer Correct Answer: A) Topoisomerase. 10. Some viruses with RNA as genetic material has been reported A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: A) True. 11. The pitch of the DNA helix (one complete turn) is A) 3.4 nm. B) 2 nm. C) 34 nm. D) 10 nm. Show Answer Correct Answer: A) 3.4 nm. 12. Escherichia coli with completely radioactive DNA was allowed to replicate in nonradioactive medium for two generations. Percentage of bacteria with radioactive DNA is A) 12.5%. B) 25%. C) 50%. D) 100%. Show Answer Correct Answer: C) 50%. 13. Coding sequence or expressed sequence is A) Exon. B) Intron. C) Structural gene. D) Regulator. Show Answer Correct Answer: A) Exon. 14. In DNA replication, the resulting daughter molecules contain one strand of the original parental DNA and one new strand. What is the explanation for this phenomenon? A) DNA replication is semiconservative. B) RNA synthesis is conservative. C) DNA replication is conservative. D) DNA replication is not conservative. Show Answer Correct Answer: A) DNA replication is semiconservative. 15. Topoisomerase A) An enzyme that keeps DNA strands from unpairing. B) An enzyme that helps relieve strain by breaking apart the DNA. C) An enzyme that untwists the DNA. D) An enzyme that helps relieve strain by breaking, swiveling, and rejoining DNA strands. Show Answer Correct Answer: D) An enzyme that helps relieve strain by breaking, swiveling, and rejoining DNA strands. 16. Which of the following rRNAs is not transcribed by RNA polymerase I? A) 28s. B) 18s. C) 5.8s. D) 5s. Show Answer Correct Answer: D) 5s. 17. Genetic code consists of-*******A. Adenine and guanine*******B. Riboflavin and ATP*******C. Cytosine and Guanine*******D. Cytosine and Uracil A) A, C, D. B) A, D. C) B, C, D. D) None of the above. Show Answer Correct Answer: B) A, D. 18. The functional unit of inheritance is A) Gene. B) Allele. C) Promoter. D) Introns. Show Answer Correct Answer: A) Gene. 19. Ribozymes are A) Specialised protein molecule. B) Phospholipid. C) Glycoprotein. D) RNA acting as catalyst. Show Answer Correct Answer: D) RNA acting as catalyst. 20. What is the function of reverse transcriptase in retroviruses? A) It hydrolyzes the host cell's DNA. B) It uses viral RNA as a template for DNA synthesis. C) It converts host cell RNA into viral DNA. D) It translates viral RNA into proteins. Show Answer Correct Answer: B) It uses viral RNA as a template for DNA synthesis. 21. Experiment called the unequivocal proof of DNA being genetic material was performed by A) Marshall Nirenberg and Hargobind Khorana. B) Avery, Macleod, and McCarty. C) Alfred Hershey and Martha Chase. D) Francis Crick and James Watson. Show Answer Correct Answer: C) Alfred Hershey and Martha Chase. 22. Which of the following gene encodes for repressor protein of lac operon A) LacI. B) LacZ. C) LacY. D) LacA. Show Answer Correct Answer: A) LacI. 23. 5' end of a polynucleotide chain contains A) Hydroxyl group. B) Phosphate group. C) Carboxyl group. D) Ethyl group. Show Answer Correct Answer: B) Phosphate group. 24. Which of the following cannot act as inducer? A) Glucose. B) Lactose. C) Galactos. D) Both (a) and (c). Show Answer Correct Answer: D) Both (a) and (c). 25. DNA is a better genetic material than RNA because, DNA lacks A) Ability to slowly mutate. B) 5-methyl uracil in place of uracil. C) 2'OH group in the sugar of its nucleotides. D) Ability to generate its replica. Show Answer Correct Answer: C) 2'OH group in the sugar of its nucleotides. ← PreviousNext →Related QuizzesClass 12 Biology Chapter 6 Molecular Basis Of Inheritance Quiz 1Class 12 Biology Chapter 6 Molecular Basis Of Inheritance Quiz 2Class 12 Biology Chapter 6 Molecular Basis Of Inheritance Quiz 3Class 12 Biology Chapter 6 Molecular Basis Of Inheritance Quiz 4Class 12 Biology Chapter 6 Molecular Basis Of Inheritance Quiz 5Class 12 Biology Chapter 6 Molecular Basis Of Inheritance Quiz 6Class 12 Biology Chapter 6 Molecular Basis Of Inheritance Quiz 7Class 12 Biology Chapter 6 Molecular Basis Of Inheritance Quiz 8Class 12 Biology Chapter 6 Molecular Basis Of Inheritance Quiz 9Class 12 Biology Chapter 6 Molecular Basis Of Inheritance Quiz 10 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books