This quiz works best with JavaScript enabled. Home > Cbse > Class 12 > Science > Biology > Class 12 Biology Chapter 6 Molecular Basis Of Inheritance – Quiz 13 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Biology Chapter 6 Molecular Basis Of Inheritance Quiz 13 (60 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. Select the correct role to complete:AUG codes for methionine and serves as ..... codon. A) Overlapping. B) Start. C) Nonsense. D) Stop. Show Answer Correct Answer: B) Start. 2. In what phase of the cell cycle does DNA replication take place? A) S. B) M. C) G2. D) G1. Show Answer Correct Answer: A) S. 3. Meselson and Stahl experiment proved A) Transformation. B) Semi Conservative DNA replication. C) Central Dogma. D) DNA is genetic material. Show Answer Correct Answer: B) Semi Conservative DNA replication. 4. Okazaki fragments are seen during A) Transcription. B) Translation. C) Transduction. D) Replication. Show Answer Correct Answer: D) Replication. 5. In a DNA stand the nucleotide are linked together by A) Phophodiester bonds. B) Peptide bonds. C) Hydrogen bonds. D) Glycosidic bonds. Show Answer Correct Answer: A) Phophodiester bonds. 6. Which enzyme is responsible for adding nucleotides to the free three prime end A) Helicase. B) Topoisomerase. C) DNA Polymersase 1TagsDNA replication enzymes. D) DNA Polymersase 3. Show Answer Correct Answer: D) DNA Polymersase 3. 7. Adenine forms ..... hydrogen bonds with Thymine from opposite strand and vice-versa. Similarly, Guanine is bonded with Cytosine with ..... H-bonds. A) Three, three. B) Two, three. C) Two, two. D) Three, two. Show Answer Correct Answer: B) Two, three. 8. Nucleotide arrangement in DNA can be seen by A) X-ray crystallography. B) Electron microscope. C) Ultra centrifuge. D) Transcriptase. Show Answer Correct Answer: A) X-ray crystallography. 9. Who discovered the process of transformation and on which species was it done? A) Frederich Miescher, Streptococcus pneumoniae. B) Martha Chase, T2 bacteriophage. C) Alfred Hershey, T2 Bacteriophage. D) Frederick Griffith, Streptococcus pneumoniae. Show Answer Correct Answer: D) Frederick Griffith, Streptococcus pneumoniae. 10. ERF1 is the release factor in eukaryotes that requires A) ATP for its binding to ribosome. B) GTP for its binding to ribosomes. C) ATP and GTP for its binding to ribosome. D) Mn for its binding to ribosomes. Show Answer Correct Answer: B) GTP for its binding to ribosomes. 11. What is the role of DNA ligase in the elongation of the lagging strand during DNA replication? A) It synthesizes RNA nucleotides to make a primer. B) It stabilizes the unwound parental DNA. C) It joins Okazaki fragments together. D) It unwinds the parental double helix. Show Answer Correct Answer: C) It joins Okazaki fragments together. 12. What is the role of histones in DNA packaging in eukaryotes? A) Wrap DNA around to form nucleosomes. B) Provide energy for replication. C) Repair damaged DNA. D) Act as DNA polymerases. Show Answer Correct Answer: C) Repair damaged DNA. 13. RNA and DNA are similar in terms that both A) Are double stranded. B) Have similar sugars. C) Have similar pyrimidines. D) Are polymers of nucleotides. Show Answer Correct Answer: D) Are polymers of nucleotides. 14. Individuals with the disorder xeroderma pigmentosum are hypersensitive to sunlight, and mutations to the DNA in their skin cells are left uncorrected. Why are the mutations not corrected in individuals with this disorder? A) The disorder makes cells unable to replicate DNA. B) The disorder makes cells unable to form chromosomes. C) The disorder causes cells to be unable to repair thymine dimers. D) The disorder causes mitosis to stop during metaphase. Show Answer Correct Answer: C) The disorder causes cells to be unable to repair thymine dimers. 15. Select the correct expansion to complete:UTR stands for ..... A) Untranslated Region. B) Universal Transfer RNA. C) Upstream Regulatory element. D) Unique Tandem Repeat. Show Answer Correct Answer: A) Untranslated Region. 16. Why is it that DNA replication is so much more difficult in the lagging strand compared to the leading strand? A) The leading strand replicates in the 5' to 3' direction away the replication fork. B) The lagging strand replicates in the 5' to 3' away from the replication fork. C) The leading strand has special enzymes that make the process more efficient. D) The lagging strand is parallel to the leading strand. Show Answer Correct Answer: B) The lagging strand replicates in the 5' to 3' away from the replication fork. 17. Which one of the following is the start codon? A) UGA. B) UAA. C) AUG. D) UAG. Show Answer Correct Answer: C) AUG. 18. You share the exact same DNA as your family members. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: B) False. 19. In Prokaryotes RNA polymerase is of how many types A) 3. B) 2. C) 4. D) None of these. Show Answer Correct Answer: D) None of these. 20. Choose the option with all correct statements-I) RNA polymerase I transcribes 28 S, 18S, 5.8 S rRNAII) RNA polymerase III transcribes 5S rRNA & t RNAIII) RNA polymerase II transcribes hn RNAIV) in prokaryotes different RNA polymerase transcribes mRNA, t RNA & r RNA A) I, IV & III. B) II, III & IV are correct. C) III & IV. D) I, II & III. Show Answer Correct Answer: D) I, II & III. 21. The equivalent of a structural gene is: A) Recon. B) Cistron. C) Muton. D) Operon. Show Answer Correct Answer: B) Cistron. 22. Histone proteins are rich in A) Glutamic acid. B) Lysine. C) Arginine. D) Both b and c. Show Answer Correct Answer: D) Both b and c. 23. The double helical structure of DNA was discovered in ..... A) 1928. B) 1954. C) 1953. D) 1958. Show Answer Correct Answer: C) 1953. 24. Which RNA bases would pair with TAC in transcription? A) ATG. B) GCA. C) GCA. D) AUG. Show Answer Correct Answer: D) AUG. 25. This enzyme is responsible for creating telomeres added to the ends of DNA A) DNA Helicase. B) DNA PrimaseTagsDNA replication enzymes. C) Telomerase. D) Topoisomerase. Show Answer Correct Answer: C) Telomerase. 26. All amino acids are coded by only one codon. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: B) False. 27. Which of the following amino acid is coded by a single codon? A) Arginine. B) Tryptophan. C) Phenylalanine. D) Lysine. Show Answer Correct Answer: B) Tryptophan. 28. What does "lac" refer to in what we call the lack Oberon? A) The number 1, 00, 000. B) Lac insect. C) Lactose. D) Lactase. Show Answer Correct Answer: C) Lactose. 29. The T phage is structurally made up of A) RNA and protein. B) DNA and RNA. C) DNA and protein. D) DNA and carbohydrate. Show Answer Correct Answer: C) DNA and protein. 30. The tryptophan operon is a repressible operon that is ..... ? ..... A) Permanently turned on. B) Turned off only when glucose is present in the growth medium. C) Turned off whenever tryptophan is added to the growth medium. D) Turned on only when glucose is present in the growth medium. Show Answer Correct Answer: C) Turned off whenever tryptophan is added to the growth medium. 31. Which of the following characteristics would you expect of a eukaryotic organism that lacks the enzyme telomerase? A) An inability to repair thymine dimers. B) A reduction in chromosome length in gametes. C) A high probability of somatic cells becoming cancerous. D) An inability to produce Okazaki fragments. Show Answer Correct Answer: B) A reduction in chromosome length in gametes. 32. How many codons code for amino acids? A) 64. B) 60. C) 63. D) 61. Show Answer Correct Answer: D) 61. 33. The nucleosome structure of eukaryotic chromatin is due to all of the following histones, except A) H2A. B) H1. C) H2B. D) H3. Show Answer Correct Answer: B) H1. 34. During post transcriptional processing, splicing involves A) Removal of introns and joining of exons. B) Formation of hnRNA. C) Addition of 200-300 adenylate residues at 3' end of hnRNA. D) All of the above. Show Answer Correct Answer: A) Removal of introns and joining of exons. 35. If one strand of DNA has the nitrogenous base sequence at ATCTG, what would be the complementary RNA strand sequence A) ATCGU. B) TTAGU. C) UAGAC. D) AACTG. Show Answer Correct Answer: C) UAGAC. 36. The RNA polymerase that transcribes 18S and 28S rRNA in eukaryotes is: A) RNA polymerase I. B) RNA polymerase IV. C) RNA polymerase II. D) RNA polymerase III. Show Answer Correct Answer: A) RNA polymerase I. 37. In the Hershey-Chase experiment A) DNA was labeled with radioactive sulfur. B) Most of the phage DNA never entered the bacteria. C) DNA from parent bacteriophage appeared in progeny bacteriophages. D) More than three-fourths of the phage protein appeared in progeny phages. Show Answer Correct Answer: C) DNA from parent bacteriophage appeared in progeny bacteriophages. 38. Which of the following methodology is used to identify all the genes that are expressed as RNA in Human Genome Project (HGP)? A) Sequence Annotation. B) Ammonification. C) Karyotyping. D) Expressed Sequence Tags. Show Answer Correct Answer: D) Expressed Sequence Tags. 39. DNA polymerase-******A. Is the main enzyme for RNA synthesis******B. Is DNA dependent DNA polymerising enzyme******C. Is highly efficient enzyme******D. It catalyses reaction with high degree of accuracy A) C, D. B) A, B, C, D. C) A, B, C. D) B, C, D. Show Answer Correct Answer: D) B, C, D. 40. The error rate of changing an incorrect base with another incorrect base during proofreading is A) 1 in 10 bases. B) 1 in 10, 000 bases. C) 1 in 100 bases. D) 1 in 1000 bases. Show Answer Correct Answer: B) 1 in 10, 000 bases. 41. Peptidyl transferase enzyme is present in A) Messenger RNA. B) Transfer RNA. C) Ribosomal RNA. D) Small Nuclear RNA. Show Answer Correct Answer: C) Ribosomal RNA. 42. Which is correct about Primase- A) It is DNA polymerase. B) It is RNA polymerase. C) It is DNA dependent RNA polymerase. D) Both A and C. Show Answer Correct Answer: C) It is DNA dependent RNA polymerase. 43. Distance between two conjugative base pairs is A) 3.4nm. B) 3.2 Armstrong. C) 0.34 nm. D) None of the above. Show Answer Correct Answer: C) 0.34 nm. 44. First experimental proof for semi-conservative DNA replication was shown in: A) Neurospora crassa. B) Escherichia coli. C) Rattus rattus. D) Streptococcus pneumonia. Show Answer Correct Answer: B) Escherichia coli. 45. Which is required for protein synthesis? A) Initiation codon. B) GTP. C) Peptidyl transferase. D) All of these. Show Answer Correct Answer: D) All of these. 46. Which one-of the following is not a part of a transcription unit in DNA? A) A terminator. B) The inducer. C) The structural gene. D) A promoter. Show Answer Correct Answer: B) The inducer. 47. Synthesis of DNA is A) Pseudogonic. B) Spontaneous. C) Exergonic. D) Endergonic. Show Answer Correct Answer: D) Endergonic. 48. Select the correct expansion:SSBPs stand for ..... A) Single Stranded Binding Proteins. B) Small Subunit Binding Proteins. C) Supercoiled Strand Binding Proteins. D) Sequence Specific Binding Proteins. Show Answer Correct Answer: A) Single Stranded Binding Proteins. 49. Approximately how many base pairs (bp) are present in a typical nucleosome? A) 400 bp. B) 200 bp. C) 300 bp. D) 100 bp. Show Answer Correct Answer: B) 200 bp. 50. The year 2003 was celebrated as the 50th anniversary of the discovery of: A) Transposons by Barbara McClintock. B) Mendel's laws of inheritance. C) Structure of DNA by Watson and Crick. D) Biotechnology by Kary Mullis. Show Answer Correct Answer: C) Structure of DNA by Watson and Crick. 51. Helicase breaks hydrogen bonds between DNA strands. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: A) True. 52. 30% of the bases in a sample DNA extracted from eukaryotic cell is a Denise. What percentage of cytocine is present on this DNA? A) 10%. B) 20%. C) 40%. D) 30%. Show Answer Correct Answer: B) 20%. 53. Which of the following best explains how mutations in DNA can result in the expression of anew phenotype? A) Nucleic acids are methylated. B) The gene is now read in the 3' to 5' direction. C) The polarity of lRNA becomes the opposite of that of DNA. D) A different polypeptide is produced. Show Answer Correct Answer: D) A different polypeptide is produced. 54. Select the correct process to complete:Enhancers increase the rate of ..... A) Splicing. B) Replication. C) Translation. D) Transcription. Show Answer Correct Answer: D) Transcription. 55. DNA fingerprint pattern of a child is A) Exactly similar to both the parents. B) 100% similar to father. C) 100% similar to mother. D) 50% similar to father and 50% similar to mother. Show Answer Correct Answer: D) 50% similar to father and 50% similar to mother. 56. RNA primer is removed by A) DNAP-III. B) DNAP-II. C) DNA-P-I. D) Primase. Show Answer Correct Answer: C) DNA-P-I. 57. Which of the following transcription termination technique has RNA dependent ATPase activity? A) Rifampcin. B) Rho independent. C) Intercalating agents. D) Rho dependent. Show Answer Correct Answer: D) Rho dependent. 58. Select the correct regions to complete:DNA fingerprinting relies on ..... regions. A) RRNA genes. B) Exonic coding regions. C) Centromeric repeats only. D) VNTR regions. Show Answer Correct Answer: D) VNTR regions. 59. In the Watson-Crick model of DNA, the two strands are held together by: A) Covalent bonds between purines and pyrimidines. B) Hydrogen bonds between complementary bases. C) Van der Waals forces between sugar molecules. D) Ionic bonds between phosphate groups. Show Answer Correct Answer: B) Hydrogen bonds between complementary bases. 60. In Lac operon which of the following regulates the switching on and off of the operon? A) Lactose. B) Repressor protein. C) $\beta$. D) Permease. Show Answer Correct Answer: A) Lactose. ← PreviousNext →Related QuizzesScience QuizzesClass 12 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 8 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books