This quiz works best with JavaScript enabled. Home > Class 12 > Class 12 Biology Chapter 6 Molecular Basis Of Inheritance – Quiz 7 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Biology Chapter 6 Molecular Basis Of Inheritance Quiz 7 (25 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. A biochemist isolates, purifies, and combines in a test tube a variety of molecules needed for DNA replication. When she adds some DNA to the mixture, replication occurs, but each DNA molecule consists of a normal strand paired with numerous segments of DNA a few hundred nucleotides long. What has she probably left out of the mixture? A) DNA polymerase. B) Primase. C) DNA ligase. D) Okazaki fragments. Show Answer Correct Answer: C) DNA ligase. 2. Which of the following codons acts as both start codon and codes for methionine? A) UUG. B) AUG. C) GUG. D) UAA. Show Answer Correct Answer: B) AUG. 3. Removal of introns and joining of exons is called A) Capping. B) Tailing. C) Splicing. D) All. Show Answer Correct Answer: C) Splicing. 4. The structure in chromatin seen as 'beads-on string' when viewed under electron microscope are called A) Chromosomes. B) Nucleotides. C) Nucleosomes. D) Histone octamer. Show Answer Correct Answer: C) Nucleosomes. 5. What element(s) do all eukaryotic promoter regions share? A) Transcription factors. B) Enhancers that accept binding agents. C) A basal promoter (TATA box). D) All of these. Show Answer Correct Answer: D) All of these. 6. Which of the following types of cells are affected most by telomere shortening? A) Only eukaryotic cells. B) Only animal cells. C) Cells in prokaryotes and eukaryotes. D) Only prokaryotic cells. Show Answer Correct Answer: A) Only eukaryotic cells. 7. The anti-parallel nature of DNA is due to A) Its charged phosphate groups. B) The formation of hydrogen bonds between bases from opposite strands. C) The opposite direction of the two strands. D) The pairing of bases on one strand with bases on the other strand. Show Answer Correct Answer: C) The opposite direction of the two strands. 8. The process of transformation is not affected by which of the following enzymes? A) DNase. B) RNase. C) Lipase. D) Peptidase. Show Answer Correct Answer: D) Peptidase. 9. Which of the following RNAs should be most abundant in animal cell? A) T RNA. B) M RNA. C) Mi RNA. D) R RNA. Show Answer Correct Answer: D) R RNA. 10. Which of the following is a salient feature of the DNA double-helix structure? A) Ribose sugar forms the backbone. B) Uracil pairs with adenine. C) Complementary base pairing stabilizes the strands. D) Peptide bonds hold bases together. Show Answer Correct Answer: C) Complementary base pairing stabilizes the strands. 11. The process of transformation is not affected by which of the following enzymes?a) DNaseb) RNasec) Peptidased) Lipase A) A, B. B) A, B, C, D. C) B, C, D. D) A, B, C. Show Answer Correct Answer: C) B, C, D. 12. The process of removal of introns by endonuclease enzyme and joining of exon by ligase enzyme. A) Capping. B) Spicing. C) Tailing. D) Splicing. Show Answer Correct Answer: D) Splicing. 13. Virus A) A virus is a little more than DNA (or sometimes RNA) enclosed by a protective coat, often simply protein. B) A virus is a non-living organism. C) A virus can survive outside of a host indefinitely. D) A virus is a type of bacteria that infects human. Show Answer Correct Answer: A) A virus is a little more than DNA (or sometimes RNA) enclosed by a protective coat, often simply protein. 14. The amino acid attaches to the mRNA at its A) 5' end. B) 3' end. C) Anticodon site. D) DHU LOop. Show Answer Correct Answer: B) 3' end. 15. The spontaneous loss of amino groups from adenine in DNA results in hypoxanthine, an uncommon base, opposite thymine. What combination of proteins could repair such damage? A) DNA ligase, replication fork proteins, adenylyl cyclase. B) Telomerase, helicase, single-strand binding protein. C) Telomerase, primase, DNA polymerase. D) Nuclease, DNA polymerase, DNA ligase. Show Answer Correct Answer: D) Nuclease, DNA polymerase, DNA ligase. 16. Which of the following statements accurately describes one characteristic of histones? A) Histone H1 is not present in the nucleosome bead; instead, it draws the nucleosomes together. B) Each nucleosome consists of two molecules of histone H1. C) The carboxyl end of each histone extends outward from the nucleosome and is called a "histone tail.". D) Histones are found in mammals, but not in other animals or in plants or fungi. Show Answer Correct Answer: A) Histone H1 is not present in the nucleosome bead; instead, it draws the nucleosomes together. 17. In the base sequence of one strand of DNA isCAT, TAG, CAT, CAT, GAC what would be thebase sequence of its complementary m-RNA- A) GUA, GUA, CUG, AUC, CUG. B) AUG, CUG, CUC, GUA, CUG. C) GUA, AUC, GUA, GUA, CUG. D) GUC, CUG, CUG, CUA, CUU. Show Answer Correct Answer: C) GUA, AUC, GUA, GUA, CUG. 18. What is the consequence of a failure in cell division after DNA replication? A) Apoptosis. B) Polyploidy. C) Aneuploidy. D) Mutations. Show Answer Correct Answer: B) Polyploidy. 19. Which 2 molecules forms the sides (backbone) of the DNA ladder? A) Deoxyribose and nitrogenous base. B) Deoxyribose and a hydrogen bond. C) Nitrogenous base and phosphate. D) Deoxyribose (sugar) and phosphate. Show Answer Correct Answer: D) Deoxyribose (sugar) and phosphate. 20. DNA replication in eukaryotes starts from a single origin. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: B) False. 21. In a healthy eukaryotic cell, the rate of DNA repair is typically equal to the rate of DNA mutation. When the rate of repair lags behind the rate of mutation, what is a possible fate of the cell? A) DNA replication will proceed more quickly. B) DNA replication will continue by a new mechanism. C) The cell can be transformed into a cancerous cell. D) RNA may be used instead of DNA as inheritance material. Show Answer Correct Answer: C) The cell can be transformed into a cancerous cell. 22. A DNA with unequal nitrogen bases would most probably be A) Single stranded. B) Double stranded. C) Four stranded. D) None of the above. Show Answer Correct Answer: A) Single stranded. 23. Antiparallel A) Antiparallel refers to the arrangement of two molecules in a zigzag pattern. B) Antiparallel refers to the arrangement of two molecules in a circular shape. C) Antiparallel refers to the arrangement of two molecules in the same direction. D) Antiparallel refers to the arrangement of two molecules in opposite directions. Show Answer Correct Answer: D) Antiparallel refers to the arrangement of two molecules in opposite directions. 24. Which of the following steps in transcription is catalyzed by RNA polymerase? A) Initiation. B) All of the above. C) Elongation. D) Termination. Show Answer Correct Answer: B) All of the above. 25. In RNA, uracil pairs with A) A. B) G. C) C. D) T. Show Answer Correct Answer: A) A. ← 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 8Class 12 Biology Chapter 6 Molecular Basis Of Inheritance Quiz 9Class 12 Biology Chapter 6 Molecular Basis Of Inheritance Quiz 10Class 12 Biology Chapter 6 Molecular Basis Of Inheritance Quiz 11 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books