This quiz works best with JavaScript enabled. Home > Biology > Molecular Biology – Quiz 57 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Molecular Biology Quiz 57 (20 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. Which of the following terms refers to a segment of DNA the controls the expression of a trait? A) Chromosome. B) Chromatid. C) Gene. D) Histone. Show Answer Correct Answer: C) Gene. 2. What is the function of the poly-A tail in mRNA? A) To add modified guanin to the 3' end of the mRNA. B) To indicate the site of translational termination. C) To code for the binding of RNA polymerase to the DNA. D) To help protect the mRNA from degradation by hydrolytic enzymes. Show Answer Correct Answer: D) To help protect the mRNA from degradation by hydrolytic enzymes. 3. A mutation causing agent is called as A) Mutagen. B) Carcinogen. C) Mutation. D) All of the above. Show Answer Correct Answer: A) Mutagen. 4. In mRNA, each codon specifies a particular A) Nucleotide. B) Amino acid. C) Purine. D) Pyrimidine. Show Answer Correct Answer: B) Amino acid. 5. Cellular respiration is carried out by which of the following? A) All living organisms all of the time. B) Animals but not plants. C) Animals all of the time but plants only at night. D) Heterotrophs but not autotrophs. Show Answer Correct Answer: A) All living organisms all of the time. 6. Which enzyme is not working correctly if new DNA bases are not added to the template strand? A) DNA Polymerase. B) Topoisomerase. C) Ligase. D) Primase. Show Answer Correct Answer: A) DNA Polymerase. 7. Which enzyme is responsible for proofreading the newly composed DNA strand? A) DNA Polymerase. B) Topoisomerase. C) Ligase. D) Primase. Show Answer Correct Answer: A) DNA Polymerase. 8. A disease caused by a mutation in one or a few genes is referred to as a(n) A) Genetic disorder. B) Malfunction. C) Inheritance. D) None of above. Show Answer Correct Answer: A) Genetic disorder. 9. Which part of the cell is often called "the brain of the cell"? A) Nuclear membrane. B) Endoplasmic reticulum. C) Nucleus. D) Mitochondria. Show Answer Correct Answer: C) Nucleus. 10. All eukaryotes and prokaryotes are surrounded by a ..... A) Cell wall. B) Cell membrane. C) Cell envelope. D) Nucleus. Show Answer Correct Answer: B) Cell membrane. 11. Which is NOT a disaccharide? A) Sucrose. B) Maltose. C) Lactose. D) Galactose. Show Answer Correct Answer: D) Galactose. 12. In 1828, Friedrich Wohler artificially produced urea (organic compound) by an internal rearrangement of the atoms of ammonium cyanate (inorganic compound). What important principle did this experiment show? A) Organic compounds can be synthesised without the need of a vital force. B) Inorganic compounds are essential for living organisms. C) Organic compounds are simpler substances than inorganic compounds. D) Vitalism. Show Answer Correct Answer: A) Organic compounds can be synthesised without the need of a vital force. 13. Anything in the environment that causes a mutation is a(n) A) Splicing. B) Frameshift. C) Elongation. D) Mutagen. Show Answer Correct Answer: D) Mutagen. 14. ..... proved that DNA replicates by semiconservative replication. A) Hershey and Chase. B) Griffith. C) Messelson and Stahl. D) Franklin. Show Answer Correct Answer: C) Messelson and Stahl. 15. Intervening sequences. Do not code for any protein. Are removed during RNA processing. Found in eukaryotic DNA; not present in bacterial DNA. A) Introns. B) Exons. C) Spliceosomes. D) None of above. Show Answer Correct Answer: A) Introns. 16. What is the source of the oxygen released into the air as a product of photosynthesis? A) Chlorophyll. B) Carbon dioxide only. C) Water only. D) Both water and carbon dioxide. Show Answer Correct Answer: C) Water only. 17. What property of water makes it suitable as a coolant? A) It takes a lot of energy to increase the temperature of water. B) It takes a lot of energy for water to evaporate. C) Water molecules are cohesive and stick to the skin. D) Water is a good solvent so it can transport heat from the body. Show Answer Correct Answer: B) It takes a lot of energy for water to evaporate. 18. Group of adjacent nucleotides are joined by A) Phosphodiester bond. B) Peptide bond. C) Ionic bond. D) Covalent bond. Show Answer Correct Answer: A) Phosphodiester bond. 19. If a DNA strand ACCGTCAC is used to transcribe a piece of mRNA, what would that mRNA look like? A) ACCGUCAC. B) TGGCAGTC. C) UGGCAGUG. D) UCCGTCUC. Show Answer Correct Answer: C) UGGCAGUG. 20. What is the function of the release factor in translation? A) It separates tRNA in the A site from the growing polypeptide. B) It binds to the stop codon in the A site in place of a tRNA. C) It releases the amino acid from its tRNA to allow the amino acid to form a polypeptide. D) It releases the ribosome from the ER to allow polypeptides into the cytosol. Show Answer Correct Answer: B) It binds to the stop codon in the A site in place of a tRNA. ← PreviousNext →Related QuizzesMolecular Biology Quiz 1Molecular Biology Quiz 2Molecular Biology Quiz 3Molecular Biology Quiz 4Molecular Biology Quiz 5Molecular Biology Quiz 6Molecular Biology Quiz 7Molecular Biology Quiz 8Molecular Biology Quiz 9Molecular Biology Quiz 10 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books