This quiz works best with JavaScript enabled. Home > Agriculture > Biology > Molecular > Molecular Biology – Quiz 2 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Molecular Biology Quiz 2 (30 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. Meselson and Stahl conducted experiments using the isotopes 14N and 15N which showed that DNA replication is semi-conservative. What would they have observed about the distribution of isotopes in the DNA after one round of replication if DNA replication was conservative rather than semi-conservative? A) Only 14N DNA. B) Only 15N DNA. C) All DNA half 14N and half 15N. D) Half the DNA with only 14N and half with only 15N. Show Answer Correct Answer: D) Half the DNA with only 14N and half with only 15N. 2. What will be the sequence on the mRNA molecule that is produced when the DNA base sequence ACTGATGCC is transcribed? A) ACTGATGCC. B) ACUGAUGCC. C) UGACUACGG. D) TGACTACGG. Show Answer Correct Answer: C) UGACUACGG. 3. When people exercise and limit fluid intake, the kidneys reduce the amount of water taken from the blood to maintain balance. What best explains why less water is removed? A) Homeostasis. B) Cellular Respiration. C) Fermentation. D) Diffusion. Show Answer Correct Answer: A) Homeostasis. 4. What do the lines between the A-T and G-C pairs represent? A) Ionic bonds. B) Hydrogen bonds. C) Covalent bonds. D) Van der walls forces. Show Answer Correct Answer: B) Hydrogen bonds. 5. In E. coli, there is a mutation in a gene called dnaB that alters the DNA helicase that normally acts at the origin. Which of the following would you expect as a result of this mutation? A) No replication fork will be formed. B) Replication will occur via RNA polymerase alone. C) The DNA will supercoil. D) No proofreading will occur. Show Answer Correct Answer: A) No replication fork will be formed. 6. Which is true about active transport? A) It requires energy. B) It moves substances down the concentration gradient. C) It does not require energy. D) It moves material from high to low concentration. Show Answer Correct Answer: A) It requires energy. 7. ..... is important characteristics of IS sequence 5' - 3' end 5 - 11bps are generated from target site DNA A) Direct repeat. B) Indirect repeat. C) Inverted repeat. D) None of above. Show Answer Correct Answer: A) Direct repeat. 8. Sickle Cell Anemia is caused by a "point" mutation. Which of the following correctly describes this type of mutation? A) A nucleotide or group of nucleotides is inserted into the wrong location in the DNA. This changes the order in which the nucleotides are "read" and results in the synthesis of an incorrect amino acid sequence. B) A nucleotide or group of nucleotides is deleted from the DNA. This changes the order in which the nucleotides are "read" and results in the synthesis of an incorrect amino acid sequence. C) An incorrect nucleotide is substituted for the correct nucleotide. This changes one codon in the gene sequence. This results in a change in one amino acid in the protein. This change in one amino acid changes the overall shape/function of the protein. D) Several incorrect nucleotides are substituted for their correct counterparts. This changes several of the amino acids in the protein and results in a protein that is misshapen and not functional. Show Answer Correct Answer: C) An incorrect nucleotide is substituted for the correct nucleotide. This changes one codon in the gene sequence. This results in a change in one amino acid in the protein. This change in one amino acid changes the overall shape/function of the protein. 9. A process in which DNA has the unique ability to make an exact copy of itself. A) Replication. B) Translation. C) Transcription. D) None of above. Show Answer Correct Answer: A) Replication. 10. At room temperature, water is a liquid and methane is a gas. Which molecular property explains this difference? A) Higher molecular mass of water. B) Presence of more hydrogen in methane. C) Higher boiling point than methan. D) Dipolarity of water. Show Answer Correct Answer: D) Dipolarity of water. 11. Amino acids are the building blocks of A) Protein. B) Minerals. C) Fats. D) Carbohydrates. Show Answer Correct Answer: A) Protein. 12. How many nitrogen bases would code for a polypeptidethat is 30 amino acids long? A) 30. B) 60. C) 90. D) 10. Show Answer Correct Answer: C) 90. 13. Which of these is in order from largest to smallest. A) Chromosome, nucleus, cell, DNA, nucleotide. B) Cell, nucleotide, DNA, chromosome, nucleus. C) Cell, nucleus, chromosome, DNA, nucleotide. D) Nucleotide, DNA, chromosome, nucleus, cell. Show Answer Correct Answer: C) Cell, nucleus, chromosome, DNA, nucleotide. 14. Which enzyme help in the synthesis of ATP A) Enolase. B) ATP Synthase. C) Hexokinase. D) None of above. Show Answer Correct Answer: B) ATP Synthase. 15. If a section of a gene with the base sequence ATTGC is transcribed, what is the sequence of the RNA made? A) UUUGC. B) TAACG. C) UAACG. D) AUUGC. Show Answer Correct Answer: C) UAACG. 16. Which molecule provided by plants accounts for the energy in an animal's diet? A) Oxygen. B) Protein. C) Glucose. D) Salt. Show Answer Correct Answer: C) Glucose. 17. What is the amino acid code for start codon? A) Met. B) Phe. C) Ile. D) Leu. Show Answer Correct Answer: A) Met. 18. Why do we sweat? When water evaporates, it ..... a lot of energy from the system due to the fact that it has a high latent heat of evaporation. This is felt as a ..... sensation. A) Adds, heating. B) Adds, cooling. C) Removes, cooling. D) Removes, heating. Show Answer Correct Answer: C) Removes, cooling. 19. James exercises for 30 minutes per day, five days a week. This moderate exercise program most likely provides which benefit? A) Loss of bone and muscle strength. B) Improvement in overall health. C) Increased blood pressure. D) Decreased energy levels. Show Answer Correct Answer: B) Improvement in overall health. 20. The shape of ribose is A) Square. B) Octagon. C) Pentagon. D) Hexagon. Show Answer Correct Answer: C) Pentagon. 21. Which is necessary for a plant to convert the energy of the sun into energy it can use? A) Glucose. B) Oxygen. C) Calcium chloride. D) Chlorophyll. Show Answer Correct Answer: D) Chlorophyll. 22. Which type of reaction is the breakdown of starch into sugars? A) Denaturation. B) Catabolic. C) Reducation. D) Condensation. Show Answer Correct Answer: B) Catabolic. 23. Which of the following is considered a protein's secondary structure? A) Alpha helices. B) Beta sheets. C) Interactions between close amino acids. D) All of the above. Show Answer Correct Answer: D) All of the above. 24. Mutations are..... A) Changes in the sequence of DNA. B) Broken chromosomes. C) Bad genes. D) None of above. Show Answer Correct Answer: A) Changes in the sequence of DNA. 25. Where does photosynthesis occur? A) Mitochondria. B) Stomata. C) Xylem. D) Chloroplast. Show Answer Correct Answer: D) Chloroplast. 26. Which of the following would be a nucleotide found in DNA A) Deoxyribose + phosphate + adenine. B) Ribose + phosphate + uracil. C) Deoxyribose + phosphate + uracil. D) Ribose + phosphate + adenine. Show Answer Correct Answer: A) Deoxyribose + phosphate + adenine. 27. Which of the following describes RNA? A) RNA is usually double-stranded and contains the base thymine. B) RNA is usually single-stranded and contains the base uracil. C) RNA is longer than DNA and uses five bases to encode information. D) RNA is made in the nucleus of eukaryotic cells and stay there to carry out its functions. Show Answer Correct Answer: B) RNA is usually single-stranded and contains the base uracil. 28. Which digestive process STARTS cellular respiration? A) Eliminating waste. B) Filtering out harmful substances. C) Breaking down food into glucose. D) Chewing up food in your mouth into smaller pieces. Show Answer Correct Answer: D) Chewing up food in your mouth into smaller pieces. 29. The induced fit model is preferred over the lock-and-key model because A) Some enzymes catalyze multiple reactions. B) All substrates have the same shape. C) The active site is a polar region. D) The enzyme and substrate match each other structurally and chemically. Show Answer Correct Answer: A) Some enzymes catalyze multiple reactions. 30. How many amino acids are coded for by this sequence of nucleotides:ATG GGA ACT CCA A) 12. B) 2. C) 4. D) 6. Show Answer Correct Answer: C) 4. ← PreviousNext →Related QuizzesBiology QuizzesAgriculture QuizzesMolecular Biology Quiz 1Molecular Biology Quiz 3Molecular Biology Quiz 4Molecular Biology Quiz 5Molecular Biology Quiz 6Molecular Biology Quiz 7Molecular Biology Quiz 8Molecular Biology Quiz 9 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books