Great Reaction Time
The Lineweaver-Burke plot is created from
a) The reciprocal of the Michaelis Menten equation
b) The inverse of absorbance v. time
c) (Vmax x S)/(Km +S)
d) Boredom
a) The reciprocal of the Michaelis Menten equation
Elevation of tissue enzymes may be used to detect:
a) Presence of toxins
b) Infectious disease
c) Tissue necrosis or damage
d) Diabetes mellitus
c) Tissue necrosis or damage
AST:ALT ratio >2 can be indicative of:
a) Normal function
b) Alcoholic hepatitis
c) Chronic viral hepatitis
d) Chronic muscle disease
b) Alcoholic hepatitis
The main purpose of the porphyrins in the body is to:
a) Carry oxygen to the tissues
b) Transport iron
c) Combine with free hemoglobin
d) Contribute to the synthesis of heme
d) Contribute to the synthesis of heme
The most sensitive indicator for alcohol-induced liver damage is:
a)ALT
b)AST
c)GGT
d)ALK
c)GGT
Enzymes:
a) Change the rate of reaction
b) Change the equilibrium constant
c) Change the reaction equilibrium point
d) Are consumed in the reaction
a) Change the rate of reaction
AST and ALT are both elevated in which of the following:
a) Muscular dystrophy
b) Viral hepatitis
c) Pulmonary emboli
d) Infectious mononucleosis
b) Viral hepatitis
An amylase clearance/creatinine clearance ratio of >8 is indicative of:
a) Acute pancreatitis
b) Macroamylasemia
c) Normal pancreatic function
d) Chronic pancreatitis
a) Acute pancreatitis
Anticoagulants such as EDTA and sodium citrate should not be used when collecting samples for enzyme assays because:
a) They can bind magnesium and give a falsely decreased result
b) They can bind magnesium and give a falsely increased result
c) They can bind zinc and give a falsely decreased result
d) They can bind zinc and give a falsely increased result
a) They can bind magnesium and give a falsely decreased result
Which should be the primary test for hepatocellular function analysis?
a) AST
b) ALT
c) ALP
d) CK
b) ALT
What is the Vmax?
a) the Michaelis Menten constant
b) the velocity rate of reaction when high amounts of substrate are present
c) the logarithmic constant of zero-order kinetics
d) the reciprocal of the affinity of the enzyme for the substrate
b) the velocity rate of reaction when high amounts of substrate are present
Serum levels of CK would be elevated in which of the following conditions?
a) Diabetes mellitus
b) Chronic renal failure
c) Duchenne type muscular dystrophy
d) Early pregnancy
c) Duchenne type muscular dystrophy
ALT:ALP Ratio >5 is most likely indicative of
a) Hepatocellular disease
b) Hepatobiliary disease
c) Pregnancy
d) Hyperparathyroidism
a) Hepatocellular disease
Which enzyme is a dimer composed of 2 subunits, B and M, that catalyzes the rephosphorylation of ADP to ATP?
a) LDH
b) AST
c) ALP
d) CK
d) CK
What test should be run to confirm exposure to organophosphates (pesticide poisoning)?
a) Aldolase
b) AST
c) ALK
d) Cholinesterase
d) Cholinesterase
A structural analog of the substrate that combines with the free enzyme and competes with the normal substrate for binding at the active site is:
a) a non-competitive inhibitor
b) an allosteric inhibitor
c) a competitive inhibitor
d) an isoenzyme
c) a competitive inhibitor
Trypsin levels would be elevated in all of the following conditions except:
a) Cystic Fibrosis
b) Chronic Renal Failure
c) Pancreatitis
d) Cholestasis
d) Cholestasis
If your ALT:AST ratio is inconclusive, what other enzyme can be tested to rule out hepatobiliary disease?
a) Alcohol dehydrogenase
b) Trypsin
c) Cholinesterase
d) GGT
d) GGT
Which enzyme is responsible for breakdown of xenobiotics and has potential use to detect early liver transplant rejection?
a) Glutathione-S-Transferase
b) Cholinesterase
c) Alcohol Dehydrogenase
d) Glutamate Dehydrogenase
a) Glutathione-S-Transferase
To confirm a patient has variegate porphyria, you should test for:
a) Protoporphyrin IX
b) 5-Aminolevulinic Acid
c) Ferrochelatase
d) Protoporphyinogen oxidase
d) Protoporphyinogen oxidase
The pH activity curves for most enzymes are somewhat:
a) ellipsoid
b) linear
c) bell-shaped
d) hyperbolic
c) bell-shaped
Which of the following enzymes is the best to evaluate liver function?
a) AST
b) GGT
c) ALT
d) LDH
c) ALT
Which of the following results would be most consistent with macroamylasemia?
a) Normal serum amylase and elevated urine amylase values
b) Increased serum amylase and normal urine amylase values
c) Increased serum and urine amylase values
d) Normal serum and urine amylase values
b) Increased serum amylase and normal urine amylase values
Which enzyme is released in inflammation and can be detected by the presence of orange granules in a blood smear?
a) Glucose-6-Phosphate Dehydrogenase
b) Myeloperoxidase
c) Lipoprotein-associated Phospholipase A2
d) Glutathione-S-Transferase
b) Myeloperoxidase
Lead exposure can result in:
a) Increased urinary ALA and coproporphyrin III
b) Overstimulation of ALA dehydratase
c) Decreased zinc protoporphyrin
d) Death in the study from Colonel Mustard
a) Increased urinary ALA and coproporphyrin III