Biochemistry I End of Year MCQs — September OmpathStudy

Biochemistry I End of Year MCQs — September 2020 (Past Paper) 100 multiple choice questions from the HBC 100/VBC 100/UPC 102 Biochemistry I end-of-year online examination, sat 3 September 2020. Questions only — no answer key. --- 1. The synthesis of Thymidine Monosphosphate (TMP) requires all BUT one; a. Folic acid b. Fluorouracil c. NADPH d. Thymidylate synthase e. dihydrofolate reductase 2. Which of the following statements is TRUE about Molisch's test for carbohydrates? a. It is negative for non-reducing sugars b. It is negative for aldo sugars c. It is positive for all carbohydrates d. It is negative for reducing sugars e. It is negative for pentoses 3. In reference to Lewis structures of PCl3 and SCl4; a. Dative bond exists in the latter but not in the former b. Both have a dative bond c. Both have a lone pair of electrons d. Dative bond exists in the former but not in the latter e. Each has three bonding pairs of electrons 4. The following are components of Coenzyme A, EXCEPT a. Ribose b. -mercaptoethylamine c. Pantothenic acid d. 3'-phosphoadenosine diphosphate (3'-PADP) e. glutamate 5. Macromolecules' three-dimensional structure is formed and maintained by the following noncovalent interactions, except. a. Hydrogen bonds b. Hydrophobic interactions c. Carbon-carbon bonds d. Ionic interactions e. Van der Waals interactions 6. Saliva has a [H3O+] of 10-8 while compound B has pOH of 6. Which one is more acidic? a. Saliva, pH 8 b. Compound B, pH 8 c. Both have equal acidity, pH 8 d. Compound B, pH 6 e. Saliva, pH 6 7. A prosthetic group of a protein is a non-protein structure that is: a. Permanently associated with the protein. b. A part of the secondary structure of the protein. c. A substrate of the protein. d. Transiently bound to the protein e. A ligand of the protein. 8. A solution with pH = 5 is than a solution with pH = 7. a. 200 times more basic b. 10 times more basic c. 10 times more acidic d. 100 times more acidic e. 2 times more basic 9. Inadequate tryptophan in the diet can lead to low levels of; a. Pyridoxine b. Vitamin C c. Pantothenic acid d. Niacin e. Vitamin A 10. Glucokinase is to be found in the liver and in the pancreatic -cells. Which of the following is NOT true about glucokinase? a. It is induced by insulin b. It is not inhibited by G-6-P c. Its affinity for glucose is higher than that of hexokinase d. Its Vmax value is higher than that of hexokinase e. Its Km is for glucose is higher than that of hexokinase 11. Which of the following is associated with type I GSD? a. Hyperuricemia b. Hypoglycemia c. All the choices are correct d. Ketosis/ketonemia e. Lactic academia 12. Aspirin: a. Inhibits cyclooxygenase b. Decreases thromboxane A2 formation c. Inhibits prostaglandin synthase d. Decreases prostaglandin formation e. Decreases leukotrienes 13. Which of the following is INCORRECT about glycogenin? a. It has an inherent catalytic power b. It is attached to the single reducing end of the glycogen core c. It is attached to the single non-reducing end of the glycogen core d. It is a protein with an essential tyrosine residue at position 194 e. It acts as an original primer in glycogen synthesis 14. What type of inhibitors does the pesticides belong to? a. Arsenic acid b. Sulfa drugs c. Malonic acid. d. Cyanides e. Organophosphate compounds 15. Which of the following enzymes does not catalyze an anaplerotic reaction? a. Malic enzyme (ME) b. Malate dehydrogenase (MDH) c. Pyruvate carboxylase (PC) d. Phosphoenolpyruvate carboxykinase (PEPCK) e. Glutamate-Oxaloacetate transaminase (GOT) 16. Which of the following metabolites would not yield glucose? a. Glucogenic amino acids b. Propionate c. Even-chain fatty acids d. TCA cycle intermediates e. Odd-chain fatty acids 17. A is associated with favism a. Kinase b. Mutase c. Isomerase d. Dehydrogenase e. Phosphatase 18. Galactosemia: a. is manifested by improved vision b. is due to defective galactose-1-phosphate uridyl transferase c. is characterized by decreased galactose levels in blood d. can be treated by including milk in the diet e. is of one type only 19. The following are all true representations of the Lineweaver-Burk equation from the transformed Hyperbolic Michaelis-Menten equation into a straight line equation, y = mx + b, EXCEPT: a. x = 1/[S] b. y-intercept is 1/Vmax c. y = 1/V d. slope = Vmax/ Km e. x-intercept is 1/Km 20. Dopamine a. does not require pyridoxal phosphate in its synthesis b. underproduction causes schizophrenia c. is a neurotransmitter catecholamine d. easily crosses the Blood Brain Barrier (BBB) e. high levels cause Parkinson's disease 21. Cysteine synthesis requires the following EXCEPT: a. homocysteine b. Vitamin B6 c. Cystathionine synthase d. serine e. -ketobutyrate 22. Bonding between atoms of elements is influenced by the following forces EXCEPT; a. Shielding effect of electrons b. Nuclear - electron attraction c. Nuclear- nuclear repulsion d. Electron -electron repulsion e. Nuclear -nuclear attraction 23. W