🧬 Biochemistry Solved MCQs with Answers

Practice 1490 approved 🧬 Biochemistry questions with verified answers from the 🧬 Medical Science subject for Pakistan exams.

1490 solved MCQs

Fructose diphosphate accumulation wouldAnswer: Stimulate glycolysis and inhibit gluconeogenesis Aldolases splits fructose 1,6 biphosphate intoAnswer: Glyceraldehyde 3- phosphate and dihydroxyacetone phosphate What would be the molecular formula for a polymer made by linking ten glucose molecules together by dehydration synthesis, if molecular formula for glucose is C6H,206?Answer: C₆₀H₁₀₂O₅₁ Glycolysis reactions take place inAnswer: Cytoplasm In the Glycolysis reaction, for each glucose conversion how many ATP's are produced?Answer: 2 An intermediate which inhibits the activity of fructose 1,6 diphos-phatase would inhibitAnswer: Gluconeogenesis Which of the following enzymes plays an important role in the Cori " cycle?Answer: Lactate dehydrogenase Regulated metabolic pathways areAnswer: All of these When living organisms are cooled below some critical body temperature, the metabolic reactions within their cells cease to function properly. This malfunction occurs becauseAnswer: There is insufficient molecular motion for substrates to interact Glycogen degradation requires the enzyme namelyAnswer: Glycogen phosphorylase and glycogen-debranching enzyme The hormones, glucagon and epinephrine, stimulate glycogen breakdown to G-6-PAnswer: Indirectly, by first stimulating adenylate cyclase to make cAMP What is the cause of the genetic disease known as Galactosemia?Answer: Absence of galactose 1-P uridyl transferase Which of the following does not occur during gluconeogenesis?Answer: The conversion of pyruvate to phosphoenolpyruvate (PEP) Which of the following characteristic enzymes of gluconeogensis is not found in the cytosol?Answer: Pyruvate carboxlyase The function of gluconeogenesis isAnswer: All of these What is the consensus N-glycosylation site in a protein sequence?Answer: Asn-Xaa-(Ser or Thr) The process not involved in the formation of glucose by gluconeo-genesis isAnswer: The conversion of oxaloacetate to glucose Each reaction in a metabolic pathway isAnswer: Catalyzed by a specific enzyme Each replication bubbles consists ofAnswer: 2 replication forks In DNA replication, one new strand is synthesized complementary to an old (parent) strand and is referred asAnswer: Semiconservative In a cesium chloride gradient, DNA labeled with ¹⁵N and centrifuged will form a bandAnswer: Below DNA containing ¹⁴N The role of primase is toAnswer: Synthesize an RNA primer to begin the elongation process Deoxyribonucleoside triphosphates, being need in the chain termination methods areAnswer: All of these What is the approximate percentage of repetitive DNA sequences in human DNA?Answer: 20 to 30% The replication of a linear DNA molecule in a eukaryotic chromosome creates a problem which is reported to be sorted out byAnswer: Using enzyme called telomerase The rapid appearance of HIV-1 strains that are resistant to AIDS drugs is due in part to which of the following property of its reverse transcriptase?Answer: It lacks a proofreading exonuclease The packing ratio of nucleosomes is aboutAnswer: 7 After one replication in 15N, how many bands should be observed in a cesium chloride gradient?Answer: One Reverse transcriptase producesAnswer: DNA from RNA The nicks or gaps between Okazaki fragments are eventually sealed byAnswer: DNA ligase