This section contains 65 multiple-choice questions (MCQs) covering various aspects of clinical enzymology. These questions are designed to test your understanding of enzyme function, clinical applications, and diagnostic techniques. Each question is carefully crafted to assess your knowledge and critical thinking skills in this important field of medical science.
- Which of the following enzymes has the longest half-life?
- A. CK-MM
- B. ALP ✅
- C. Lipase
- D. LD5
- Which of the following CK isoenzymes has the longest half-life?
- A. CK-MM ✅
- B. CK-MB
- C. CK-BB
- D. CK4
- In enzymology, one international unit is the quantity of enzyme which catalyzes one micromole of substrate per minute. The catalytic enzyme activity of a sample is expressed in:
- A. Units per liter
- B. Milliunits per liter
- C. kilounits per liter
- D. all of these ✅
- Type 1 macroenzymes have been described for the following diagnostically relevant enzymes, except:
- 1. ALT
- 2. ALP
- 3. ACP
- 4. AST
- A. only 1 and 3 are correct
- B. only 2 and 4 are correct
- C. only 1, 2, and 3 are correct
- D. 1, 2, 3, and 4 are correct ✅
- These are individual-specific enzyme forms which are coded by allelic genes. The multiple forms of an enzyme are inherited according to Mendelian laws.
- A. Isoenzymes
- B. Macroenzymes type 1
- C. Alleloenzymes ✅
- D. Macroenzymes type 2
- Enzyme important in the diagnosis of organophosphate poisoning and liver parenchymal damage:
- A. LD
- B. Cholinesterase ✅
- C. CK
- D. GGT
- Enzyme important for the diagnosis of liver parenchymal damage, myocardial infarction, hemolysis, ineffective erythropoiesis, lymphoma:
- A. ALT
- B. AST
- C. LD ✅
- D. CK
- Which of the following enzyme patterns is correct in severe cardiac muscle damage with cell necrosis:
- A. CK > LDH > AST > ALT ✅
- B. LDH > CK > ALT > AST
- C. AST > ALT > CK > LDH
- D. ALT > CK > LDH > AST
- Which of the following enzyme patterns is correct in severe skeletal muscle damage with cell necrosis:
- A. CK > LDH > AST > ALT ✅
- B. LDH > CK > ALT > AST
- C. AST > ALT > CK > LDH
- D. ALT > CK > LDH > AST
- Which of the following enzyme ratios is used for the differentiation between acute alcoholic hepatitis and acute viral hepatitis:
- A. GGT/AST ✅
- B. LD/CK
- C. AST/ALT
- D. GGT/GLD
- The increase in ALP is particularly marked in people of Lewis-positive blood group:
- A. A
- B. B
- C. AB
- D. O ✅
- Which enzyme decreases markedly with age in men while increases with age are measured in women:
- A. ALP
- B. ALT
- C. AST
- D. CK ✅
- Alcoholism leads to increased activities of:
- 1. GGT
- 2. ALT
- 3. AST
- 4. GLD
- A. only 1 and 3 are correct B. only 2 and 4 are correct
- C. only 1, 2, and 3 are correct
- D. 1, 2, 3, and 4 are correct ✅
- Which of the following diseases can cause a decrease in total ALP?
- 1. Pituitary dwarfism
- 2. Liver metastases
- 3. Malnutrition
- 4. Rickets
- A. only 1 and 3 are correct ✅
- B. only 2 and 4 are correct
- C. only 1, 2, and 3 are correct
- D. 1, 2, 3, and 4 are correct
- Which of the following migration patterns is correct in the anodal separation of serum ALP at an alkaline pH on cellulose acetate strip?
- A. placental ALP > liver ALP > bone ALP > intestinal ALP > bile duct ALP
- B. bile duct ALP > liver ALP > bone ALP > intestinal ALP > placental ALP ✅
- C. liver ALP > bone ALP > bile duct ALP > intestinal ALP > placental ALP
- D. intestinal ALP > liver ALP > placental ALP > bile duct ALP > bone ALP
- Which form of ALP can be differentiated on the basis of the greater inhibition of its activity by L-phenylalanine, lesser inhibition by homoarginine and its resistance to heat when heated at 65C for 10 minutes?
- A. Placental ✅
- B. Liver
- C. Bone
- D. Bile duct
- This form of ALP is thought to be a multienzyme plasma membrane complex or a complex of the liver isoenzyme with lipoprotein X. This multiple form of ALP is found in cholestatic and metastatic liver disease even when total ALP is still normal.
- A. Liver ALP
- B. Germ cell ALP
- C. High-molecular mass ALP ✅
- D. Intestinal ALP
- This form of ALP is not normally found in the serum of healthy people and detectable in patients with seminoma of the testes, ovarian carcinoma, pituitary tumors, and thymic tumors.
- A. Liver ALP
- B. Germ cell ALP ✅
- C. High-molecular mass ALP
- D. Intestinal ALP
- This form of ALP is produced by the enterocytes and released into the blood in large quantities, particularly in B and O secretors.
- A. Liver ALP
- B. Germ cell ALP
- C. High-molecular mass ALP
- D. Intestinal ALP ✅
- This is a multiple ALP form which is biochemically a heterodimer of placental ALP and intestinal ALP. It is found in hepatocellular carcinoma and renal cell carcinoma.
- A. Placental ALP
- B. Kasahara ALP ✅
- C. Bone ALP
- D. Germ cell ALP
- Which of the following are inhibitors of ALP?
- 1. Citrate
- 2. Oxalate
- 3. EDTA
- 4. Heparin
- A. only 1 and 3 are correct
- B. only 2 and 4 are correct
- C. only 1, 2, and 3 are correct ✅
- D. 1, 2, 3, and 4 are correct
- Which of the following drugs can decrease ALP activity?
- A. Oral contraceptives ✅
- B. Allopurinol
- C. Valproic acid
- D. Oxacillin
- In amylase assays, which of the following are measured as end products?
- 1. 2-chloro-4-nitrophenol
- 2. P-nitrophenyl maltoheptaoside
- 3. 4-nitrophenol
- 4. Maltotetraose
- A. only 1 and 3 are correct ✅
- B. only 2 and 4 are correct
- C. only 1, 2, and 3 are correct
- D. 1, 2, 3, and 4 are correct
- In neonates, the amylase measured consists only of:
- A. Salivary isoenzyme ✅
- B. Pancreatic isoenzyme
- C. both salivary and pancreatic
- D. none of these
- Which of the following methods are used for ACE measurement?
- 1. Liberman
- 2. Neels
- 3. Ryan
- 4. Silverstein
- A. only 1 and 3 are correct
- B. only 1, 2, and 3 are correct
- B. only 2 and 4 are correct
- D. 1,2,3 and 4 are correct ✅
