Biochemistry – MCQ

1. Hormone which act via cGMP as second messenger is-

2. Biochemical functions of choline are all except-

3. Biochemical functions of phosphatidyl Inositol are all except-

4. Pyridoxal phosphate acts as co-enzyme for all the enzymes except-

5. 75 years old farmer visited general practitioner with weakness, diarrhoea, decreased vision and purulent discharge from eyes. On examination, there were subcutaneous haemorrhage in the arms and legs. Eyes showed marked inflammation and dilatation of conjunctiva vessels and margins of eyelid, fissure at the angle of the mouth, tongue was sore and swollen. Deep tendon reflexes were diminished. Which vitamin deficiency causes changes in the eye?

6. Coenzymes are involved in transferring the groups from one substrate to another substrate. Which of the subset is a mismatch?
Co-enzyme  – Group

7. Zymogen which is dependent on the post translation modification by the vitamin K is-

8. Mother brought 2 months old baby for history of red patches under skin in the anterior region of both thighs and knee. Baby had received oral vitamin K prophylaxis at birth. Neonatal period was normal. Baby was exclusively breastfed. Laboratory investigation showed Hb- 6gm%, PT- 40 secs, normal platelet count, normal fibrinogen level. Vitamin K was administered with complete recovery. Vitamin administration acts as a coenzyme for which of the following post translational reaction?

9. Which is not true regarding the activation of vitamin D?

10. A 50-year old woman presents to her physician complaining of weakness, walking difficulty and peripheral neuritis. A careful history reveals that she is malnourished. She is found to have a severe thiamine deficiency. The function of which of the following enzymes in the citric acid cycle would be most directly affected by the riboflavin deficiency?

11. All of the following are the anaplerotic reactions of Krebs Cycle except-

12. 60-year-old man developed signs of Parkinson’s disease at the age of 47. He presented with mild resting tremors and decreased arm swing while walking. A year later he began taking 500mgof L -DOPA with peripheral decarboxylase inhibitor with excellent response. Which of the following amino acid’s metabolism is defective?

13. All of the compounds are the products of tyrosine metabolism except-

14. Glycine is the simplest, nonessential amino acid helps in formation of various compounds except-

15. Methyl transferase enzyme transfer the methyl group from the S-adenosyl methionine to the acceptor forming methylated products. All of the following are methylated product except-

16. One carbon group is utilized in the synthesis of the following compound except-

17. Identify the wrong statement with respect to metabolic functions of subcellular organelle –

18. Which of the following is not a multi enzyme complex?

19. Which of the following is not a branched chain amino acid?

20. Which of the metabolic statement regarding methionine is false.

21. Which of the following is not an essential amino acid?

22. Which of the following product is not derived from cholesterol?

23. Which of the following is wrong about Thromboxane A2?

24. A 40-year-old man presented to emergency department with one-week history of   weakness, fever, nausea, vomiting and a painful left foot with foul smelling pus discharge from ulcer on the sole.  Past history of type 2 diabetes > 6 years, dyslipidemia and hypertension. He was on gliclazide and metformin since diagnosis and mixtard was started for 6 months because of poor glycaemic control. He stopped injecting insulin for 1 week ago – poor appetite precipitated hypoglycaemia. Temperature 38.9⁰C, BP 96/60 mmHg, Pulse 140 beats/minute, respiratory rate 33 /minute, deep sighing breathing, drowsy but arousable. Tongue coated, dry mucosa and decrease skin turgor. All of the metabolic derangements have happened in this patient except-

25. Which one of the following statements concerning gluconeogenesis is not correct?

26. A young man presents with history of bloating and diarrhoea and signs of dehydration after attending birthday party, indulging on pastries and ice creams. Patient is afebrile. The patient has experienced similar episodes following ingestion of a significant number of dairy products. This clinical picture is most probably due to a deficiency in the activity of:

27. Which of the following statement is wrong about the absorption of carbohydrate.

28. Which of the following is wrong about the Rapaport-Leubering cycle?

29. In which of the following cells, anerobic metabolism does not occur?

30. Maternally inherited mitochondrial disorders are all of the following except-

31. Compounds which are formed from pyruvate are all except-

32. An 18-year-old boy was admitted to hospital with yellowish discoloration of sclerae, fatigue, and paleness, splenomegaly. His history revealed that he had suffered severe anemia since the neonatal period.  His parents were married within same family. Laboratory investigation reveals: Hb-6gm%, Peripheral smear showing marked anisopoikilocytosis, polychromia, reticulocyte count-30%, total bilirubin – 15mg/dL, conjugated bilirubin- 5mg/dL, normal haemoglobin electrophoresis, Direct coomb’s test negative. Patient suspected of chronic nonsperocytic hemolytic anemia. Enzymatic evaluation showed Pyruvate kinase – 9.7 (ref value: 11.9 – 16 U/g Hb) and rest of the red blood cell enzyme assays were normal. Which of the following statement is wrong?

33. Von Gierke’s disease involves a deficiency of which of the following enzymes-

34. 30-year-old female presents to GP with history of weakness, muscle cramps and observed reddish discoloration of urine after playing a match of shuttle badminton. She feels more as loner. Her friends find her lazy and reluctant to play. She used to feel fatigued. Which of the following enzyme deficiency would lead to this kind of presentation?

35. Key glycolytic enzymes are all except-

36. Hereditary fructose intolerance is carbohydrate metabolic error because of the deficiency of enzyme which catalyse one of the following reaction-

37. One-week old neonate presented to the hospital with mild jaundice, poor feeding, vomiting, abdominal distension. Laboratory investigation revealed abnormal liver function test and positive for urine reducing substance. On ophthalmoscopy evaluation showed cataract in both eyes. The development of the cataract is because of elevated levels of-

38. During the well-fed state insulin activates all of the following enzymes except-

39. Reduced coenzyme product derived from the HMP pathway are involved in all except-

40. Uncouplers dissipate the H⁺ gradient across the inner mitochondrial membrane and the energy is released as heat instead of ATP production. All of the following are the physiological uncouplers except-

41. Iron deficiency anemia 12 years old girl presented with 3-month history of chest discomfort on exertion, palpitation, light headedness and generalised fatigability. There is no history of loss of consciousness, significant shortness of breath. There is history of pain during defecation and constipation. She had no history of weight loss or anorexia and. During the follow up visit, patient was reluctant to reveal unusual the eating habit. Patient disclosed craving to eat chalk from past one year.  Laboratory investigation: Hb-6gm%(12-16gm%), MCV-70fl(79-90fl); MCHC-300g/Lt(32-36g/dL); Reticulocyte- 15%, Peripheral smear- microcytic hypochromic anemia.
Which of the enzyme is affected in ATP production?

42. Which of the mineral is required for the oxidative phosphorylation?

43. All of the following are antioxidant vitamin except?

44. Which of the following mineral has antioxidant role?

45. All of the following are Zinc dependent enzymes except-

46. 3-year-old boy brought to the hospital for the aggressive behaviour with lip chewing, tongue and finger biting. Laboratory report of serum uric acid is 20mg/dL (3.4-7mg/dL).
Which of the following enzyme deficiency leads to presentation of the clinical symptom?

47. Micronutrients required for the heme synthesis are all except-

48. 30-year-old man brought his routine blood reports to GP with elevated levels of alkaline phosphate. Lab reports, Serum ALP-400IU/L( reference value<130 IU/L), AST- 20 IU/L,AST- 16 IU/L, Total bilirubin- 1mg/dl. Patient complains of vague pain in his hip.
All of the following markers have isoenzymes except-

49. 18 months old female child brought to emergency department with 12-15 episodes of persistent vomiting and drowsiness, mild hepatomegaly. There is history of sudden death of previous child. Plasma glucose was 18mg/dL, Plasma ammonia- 70µmol/L ((6-50 µmol/L) Arterial blood pH-7.25, pCO₂-30mmHg, bicarbonate-15mmol/L negative for urine ketones.  Acyl carnitine profile revealed free carnitine (40 (15.5–46.7)), hexanoylcarnitine -1.02 (0–0.15), octanoylcarnitine -7.8 (0–0.27), decenoylcarnitine-1.22 (0–0.25), decanoylcarnitine-0.67 (0–0.32). Urinary organic acids showed moderately elevated hexanoylglycine, mildly increased suberylglycine and phenylpropionylglycine. No ketones and carboxylic acids.
Name the deficient enzyme in this child.

50. Which of the following is not a positive acute phase protein?

51. All of the following are the phospholipids except-

52. Heme containing proteins are all except-