CC2 LEC (P): L5 Amylase and Lipase

gd gn bnk

A

What is the alternative name for Amylase?

a. Diastase

b. Amylopsin

c. Lipase

d. Hexokinase

A

What is the formal systematic name for Amylase?

a. Alpha-1,4 Glucan-4-Glucohydrolase

b. Triacylglycerol Acylhydrolase

c. Glucose-6-Phosphate Dehydrogenase

d. Carboxylester Lipase

A

Which of the following describes the characteristic breakdown catalyzed by amylase?

a. Breakdown of starch and glycogen

b. Breakdown of long chain fatty acids

c. Breakdown of dietary triglycerides

d. Breakdown of structural proteins

A

What is the molecular weight of amylase, which makes it the smallest enzyme in size?

a. MW 50,000 to 55,000 Da

b. MW 100,000 to 120,000 Da

c. MW 10,000 to 15,000 Da

d. MW 80,000 to 95,000 Da

A

Which elements are required as co-factors for the activation of amylase?

a. Calcium and Chloride

b. Magnesium and Zinc

c. Potassium and Sodium

d. Iron and Copper

A

What are the primary tissue sources where amylase originates?

a. Pancreas, liver, and salivary glands

b. Kidneys, lungs, and heart

c. Skeletal muscle, brain, and spleen

d. Gallbladder, stomach, and intestines

A

Which specific cells in the pancreas produce amylase?

a. Acinar cells

b. Islets of Langerhans

c. Beta cells

d. Alpha cells

A

What is the specific name given to salivary amylase?

a. Ptyalin

b. Amylopsin

c. Diastase

d. Lipase

A

How does salivary amylase behave during electrophoresis?

a. It migrates fastest to the anode

b. It migrates slowest to the anode

c. It remains completely stationary at the origin

d. It migrates rapidly to the cathode

A

What substance is known to inhibit salivary amylase?

a. Wheat germ lectin

b. Morphine

c. Triolein

d. Olive oil

A

What is the specific name given to pancreatic amylase?

a. Amylopsin

b. Ptyalin

c. Diastase

d. Glucanase

A

How does pancreatic amylase behave during electrophoresis?

a. It migrates slowest to the anode

b. It migrates fastest to the anode

c. It moves exclusively toward the cathode

d. It precipitates immediately

A

What is the clinical significance of amylase regarding acute pancreatitis?

a. It is the earliest pancreatic marker

b. It is a strictly late-stage marker

c. It decreases rapidly during acute pancreatitis

d. It has no diagnostic value for acute pancreatitis

A

Following the onset of acute pancreatitis, when does amylase typically begin to rise?

a. Within 2-12 hours

b. After 24-48 hours

c. Within 5-10 minutes

d. After 3-5 days

A

At what point does amylase typically reach its peak concentration in acute pancreatitis?

a. At 24 hours

b. At 48 hours

c. At 72 hours

d. At 12 hours

A

When do amylase levels typically return to normal following an episode of acute pancreatitis?

a. Within 3-5 days

b. Within 1-2 days

c. Within 2-4 weeks

d. Within 12-24 hours

A

Why is amylase considered a non-specific marker for the pancreas?

a. It is also produced by the salivary glands

b. It is predominantly produced by cardiac muscle

c. It is constantly excreted in high amounts by the skin

d. It is heavily synthesized by the red blood cells

A

Which condition is associated with a pronounced elevation of amylase, reaching 5 times the normal limit?

a. Acute pancreatitis

b. Mumps

c. Perforated peptic ulcer

d. Salivary gland inflammation

A

Which structural pancreatic anomaly can cause a pronounced elevation (5 times the normal) of amylase?

a. Pancreatic pseudocyst

b. Pancreatic carcinoma

c. Pancreatic beta-cell adenoma

d. Pancreatic duct stricture

A

The administration of which drug is known to cause a pronounced elevation (5 times the normal) of amylase?

a. Morphine administration

b. Aspirin

c. Birth control pills

d. Thiazide diuretics

A

Which viral infection causes a moderate elevation (3 to 5 times the normal) of amylase?

a. Mumps

b. Measles

c. Rubella

d. Influenza

A

Which gastrointestinal condition leads to a moderate elevation (3 to 5 times the normal) of amylase?

a. Perforated peptic ulcer

b. Acute cholecystitis

c. Intestinal obstruction

d. Duodenal polyp

A

Which condition, presenting as a late manifestation, causes a moderate elevation of amylase?

a. Pancreatic carcinoma affecting the head of the pancreas

b. Early-stage pancreatic pseudocyst

c. Acute pancreatitis

d. Uncomplicated gallstones

A

In which body fluids can amylase be detected for diagnostic purposes?

a. Serum, urine, and peritoneal fluid

b. Cerebrospinal fluid and synovial fluid

c. Saliva and tears only

d. Whole blood and seminal fluid

B

How long is amylase stable in serum and urine when stored at room temperature?

a. For 2 months

b. For 1 week

c. For 24 hours

d. For 48 hours

A

Due to its small size, how is amylase processed by the renal system?

a. It is normally filtered by the renal glomerulus and appears in the urine

b. It is completely reabsorbed by the proximal convoluted tubule

c. It is strictly retained in the bloodstream bound to albumin

d. It is destroyed by renal medullary cells

B

How long is amylase stable in serum and urine when refrigerated at 4°C?

a. For 1 week

b. For 2 months

c. For 6 months

d. For 5 days

B

Which anticoagulants must be avoided when collecting samples for amylase testing?

a. Heparin and lithium

b. Calcium-binding anticoagulants such as citrate, oxalate and EDTA

c. Sodium fluoride and potassium oxalate

d. Acid citrate dextrose exclusively

B

Why must calcium-binding anticoagulants be avoided for amylase specimens?

a. They denature the enzyme's primary structure

b. Amylase requires calcium for activation

c. They artificially raise the sample's pH

d. They cause immediate precipitation of starches

B

Specimens for amylase analysis should strictly avoid contamination with which bodily fluid?

a. Sweat

b. Saliva

c. Urine

d. Tears

B

What is the general effect of hemolysis on amylase levels?

a. It causes a massive false decrease

b. Red cells do not contain AMS and hemolysis will not interfere except for coupled enzymatic methods

c. It directly hydrolyzes the starch substrate

d. It falsely elevates the result by releasing intracellular amylase

B

What are the preferred collection tubes for amylase analysis?

a. Green top lithium heparin tubes

b. SST (Gold)/Glass Tubes

c. Purple top EDTA tubes

d. Light blue top citrate tubes

B

How do high levels of triglycerides (TAG) affect serum amylase activity?

a. They exponentially accelerate enzyme kinetics

b. TAG suppresses or inhibits serum AMS activity

c. They permanently bind to the enzyme's active site

d. They cause a false positive in all colorimetric assays

B

Due to the inhibitory effect of triglycerides, what unusual presentation might occur in acute pancreatitis?

a. Amylase levels rise to 10 times the normal

b. Amylase may be normal in acute pancreatitis with hyperlipemia

c. Amylase completely disappears from the urine

d. Amylase permanently converts into pancreatic lipase

B

What is the physiological mechanism behind the false elevation of amylase caused by morphine and opiates?

a. They induce rapid necrosis of pancreatic acinar cells

b. They cause constriction of the sphincter of Oddi and of the pancreatic ducts

c. They directly stimulate the salivary glands to overproduce ptyalin

d. They increase renal reabsorption of amylase

B

Which of the following drugs is listed as capable of increasing amylase measurements?

a. Penicillin

b. Asparaginase

c. Metformin

d. Ibuprofen

B

Which class of diuretics can lead to increased amylase measurements?

a. Loop diuretics

b. Thiazide diuretics

c. Potassium-sparing diuretics

d. Osmotic diuretics

B

What is the universal substrate used across all methodologies for measuring amylase?

a. Olive oil

b. Starch

c. Triolein

d. Maltopentose

B

Which methodology is considered the classic reference method for amylase?

a. Amyloclastic method

b. Saccharogenic method

c. Chromogenic method

d. Turbidimetric method

B

The results of the saccharogenic method are classically expressed in which units?

a. International Units per Liter (U/L)

b. Somogyi units

c. Cherry-Crandall units

d. Bodansky units

B

What exactly does the saccharogenic method measure to determine amylase activity?

a. The rate of clearing of a cloudy solution

b. The amount of reducing sugars produced by the hydrolysis of starch

c. The degradation and disappearance of the starch substrate

d. The liberation of free fatty acids

B

How does the amyloclastic method measure amylase activity?

a. By titrating liberated fatty acids with NaOH

b. By following the decreases in substrate concentration (degradation of starch)

c. By measuring the increase in color intensity of a dye

d. By monitoring the conversion of NAD to NADH at 340 nm

B

Which amylase method is frequently used for automated procedures but encounters interference from hemolysis?

a. Saccharogenic method

b. Coupled-Enzyme Reaction or Continuous Monitoring

c. Turbidimetric method

d. Amyloclastic method

B

What specific substrates are often utilized in the coupled-enzyme reaction for amylase?

a. Triolein or olive oil

b. Maltopentose or maltotetrose

c. Polysaccharide-dye complexes

d. Free glucose and hexokinase

B

What is the optimal pH required for the coupled-enzyme reaction measuring amylase?

a. 5.0

b. 6.9

c. 8.5

d. 10.0

B

In the specific coupled reaction of Amylase-glucosidase-hexokinase-G6PD, what change is measured at 340 nm?

a. The conversion of NADH to NAD

b. The change in absorbance as NAD is converted to NADH

c. The precipitation of glucose

d. The appearance of a blue-purple color

B

What is the standard reference range for amylase in serum?

a. 5-35 U/L

b. 30-220 U/L or 60-180 SU/dL

c. < 38 U/L

d. 125-220 U/L

B

What is the normal reference range for amylase in urine?

a. 1.0-5.0 IU/h

b. 6.5-48.1 IU/h

c. 50-100 IU/h

d. 150-300 IU/h

B

Which category of pain-relieving drugs, aside from morphine specifically, leads to falsely elevated amylase levels?

a. NSAIDs

b. Opiates (codeine, meperidine)

c. Salicylates

d. Acetaminophen

C

What is the formal systematic name for Lipase?

a. Alpha-1,4 Glucan-4-Glucohydrolase

b. Glucose-6-Phosphate Dehydrogenase

c. Triacylglycerol Acylhydrolase

d. Carboxylester Hydrolase

C

In the intestines, lipase catalyzes the partial hydrolysis of dietary TAG to produce which intermediate?

a. Free glycerol

b. 3-monoglyceride

c. 2-monoglyceride

d. Phospholipids

C

Along with the 2-monoglyceride intermediate, what specific fatty acids are produced by intestinal lipase hydrolysis?

a. Short chain fatty acids

b. Medium chain fatty acids

c. Long chain fatty acids

d. Volatile fatty acids

C

Which specific enzyme is designated as the L1 isoenzyme of lipase?

a. Carboxylester Lipase

b. Salivary Lipase

c. Pancreatic Lipase

d. Hepatic Lipase

C

Which specific enzyme is designated as the L3 isoenzyme of lipase?

a. Pancreatic Lipase

b. Lipoprotein Lipase

c. Carboxylester Lipase

d. Gastric Lipase

C

In which organ is lipase primarily found?

a. Liver

b. Salivary glands

c. Pancreas

d. Kidneys

C

What is the clinical significance of lipase in relation to acute pancreatitis?

a. It is the earliest marker to rise

b. It is only useful for chronic pancreatitis

c. It is a late marker for acute pancreatitis

d. It acts as an inhibitor of pancreatic inflammation

C

How does the presence of lipase in normal urine compare to amylase?

a. It is found in much higher concentrations than amylase

b. It is filtered exactly the same way as amylase

c. It is not present in normal urine

d. It appears only during dehydration

C

How does the specificity of lipase for acute pancreatitis compare to amylase?

a. It is equally as specific as amylase

b. It is much less specific than amylase

c. It is more specific for acute pancreatitis compared to amylase

d. Neither is specific for acute pancreatitis

C

When comparing the initial elevation timelines in acute pancreatitis, how does lipase behave relative to amylase?

a. It rises exactly at the same time

b. It rises much faster

c. Rises more slowly compared to amylase

d. It drops initially before rising

C

Following the onset of acute pancreatitis, when does the serum lipase level gradually begin to increase?

a. Within 2-12 hours

b. At exactly 24 hours

c. 2-4 days after the onset

d. 1 week after the onset

C

Once elevated during acute pancreatitis, how long does serum lipase typically remain elevated?

a. For exactly 24 hours

b. For 3-5 days

c. For 5 days up to 2 weeks

d. For 1 to 2 months

C

In the context of pancreatic markers, if amylase is considered the early marker, how is lipase classified?

a. The immediate marker

b. The resolving marker

c. The late marker

d. The non-specific marker

C

Besides acute pancreatitis, which other gastrointestinal condition can cause an elevation in lipase?

a. Uncomplicated gastritis

b. Viral gastroenteritis

c. Penetrating duodenal ulcers

d. Esophageal varices

C

Which gallbladder-related condition is also known to elevate serum lipase levels?

a. Chronic cholelithiasis

b. Biliary dyskinesia

c. Acute cholecystitis

d. Porcelain gallbladder

C

If both amylase and lipase levels are found to be increased in a patient, what does the elevation in lipase specifically indicate?

a. A salivary gland problem

b. A renal failure presentation

c. That it is a pancreatic problem

d. A severe liver pathology

C

What effect does hemolysis have on lipase activity during laboratory analysis?

a. It causes a massive false increase

b. It has no effect whatsoever

c. Hemolysis can cause a false decrease in lipase activity

d. It changes the optimal pH requirement

C

Which type of specimen is preferred for lipase testing?

a. Whole blood

b. Urine

c. Serum

d. Peritoneal fluid

C

What specimen condition is known to cause a false elevation in lipase activity?

a. Exposure to light

b. High triglyceride levels

c. Specimen contaminated with bacteria

d. Use of EDTA tubes

C

Which methodology is designated as the reference method for measuring lipase?

a. Saccharogenic method

b. Turbidimetric method

c. Cherry and Crandall

d. Coupled-Enzyme Reaction

C

What substrate was originally utilized in the classic Cherry and Crandall method?

a. Starch

b. Triolein

c. Olive oil

d. Maltopentose

C

In the Cherry and Crandall method, how are the liberated fatty acids measured?

a. By spectrophotometric reading at 340 nm

b. By estimating the rate of clearing

c. By titration with NaOH

d. By complexing with a chromogenic dye directly

C

What is the required incubation period for the classic Cherry and Crandall method?

a. 30 minutes

b. 1 hour

c. 24 hour incubation

d. 48 hour incubation

C

In modern adaptations of the Cherry and Crandall method, which substrate is now used to provide a more pure form of triglycerides?

a. Olive oil

b. Butterfat

c. Maltotetrose

d. Triolein

C

In modified lipase assays, what specific chemical can be used to determine the amount of acid released without titration?

a. Silver nitrate

b. Calcium chloride

c. Barium sulfate

d. Copper salts

D

During the copper salt methodology for lipase, what do the copper ions form a complex with?

a. The unused triolein substrate

b. The glycerol backbone

c. The intact triglycerides

d. The fatty acids generated by hydrolysis

D

What distinguishes the solubility of the fatty acid-copper complex formed in the lipase assay?

a. It precipitates immediately out of water

b. It only dissolves in strong acids

c. It is completely insoluble in all aqueous solutions

d. It dissolves in water while the original substrate does not

D

In the copper salt method, what does the colorimetric measurement of copper indicate?

a. The amount of unreacted substrate remaining

b. The amount of glycerol produced

c. The level of interfering bacteria

d. The amount of fatty acids present, showing the level of enzyme activity

D

What can be added to the fatty acid-copper complex mixture to measure intensity more easily?

a. Sodium hydroxide

b. Phenazine methosulfate

c. Reducing sugars

D

Which lipase methodology is described as being simpler and more rapid than the reference method?

a. Cherry and Crandall method

b. Saccharogenic method

c. Coupled reactions with peroxidase

d. Turbidimetric Method

D

What exactly is measured in the turbidimetric method to estimate lipase activity?

a. The increase in color intensity

b. The formation of a dense precipitate

c. The liberation of carbon dioxide bubbles

d. The rate of clearing

D

In the turbidimetric method for lipase, what does a persistent cloudy appearance signify?

a. A high concentration of active lipase

b. A sample contaminated with hemoglobin

c. Complete hydrolysis of the substrate

d. High TAG (triglycerides)

D

Which enzymes are utilized in the coupled reactions for the colorimetric measurement of lipase?

a. Amylase and hexokinase

b. Glucosidase and G6PD

c. Malate dehydrogenase and NAD

d. Peroxidase or glycerol kinase

D

What is the accepted reference range for Lipase?

a. 30-220 U/L

b. 6.5-48.1 IU/h

c. 60-180 SU/dL

d. < 38 U/L

D

What is a key clinical distinction to remember between the two primary digestive enzymes discussed?

a. Amylase is only found in the liver

b. Lipase rises much faster than amylase

c. Amylase is more specific to the pancreas than lipase

d. Lipase is more specific to the pancreas

D

Which of the following statements is true regarding the physical properties of the discussed enzymes?

a. Lipase is the largest enzyme in the human body

b. Amylase has a molecular weight exceeding 150,000 Da

c. Lipase is readily filtered by the renal glomerulus

d. Amylase is the smallest enzyme in size

D

While amylase originates primarily from the pancreas and salivary glands, which other organ is noted as a source?

a. Kidneys

b. Brain

c. Lungs

d. Liver

D

What specific combination of conditions leads to the inactivation of salivary amylase?

a. Positively charged + freezing temps

b. Neutral charge + room temp

c. Strongly alkaline pH + heavy metals

d. Negatively charged + warm temp

D

What mnemonic rule is used to remember the electrophoretic migration of amylase isoenzymes?

a. FLAT

b. CRAB

c. LEAD

d. PANIC (Positive Anodal, Negative is Cathodal)

D

Which environmental or medical exposure can cause a moderate elevation of amylase?

a. Extreme cold exposure

b. Hyperbaric oxygen therapy

c. Ultraviolet light therapy

d. Ionizing radiation

D

Which common medication, often taken daily by women, is known to increase amylase measurements?

a. Antacids

b. Iron supplements

c. Multivitamins

d. Birth control pills

D

Which of the following methods measures amylase activity using maltopentose or maltotetrose as the starting substrate?

a. Saccharogenic method

b. Amyloclastic method

c. Chromogenic method

d. Coupled-Enzyme Reaction

D

In the classification of lipase isoenzymes, what is the identity of the L2 isoenzyme?

a. Carboxylester Lipase

b. Salivary Lipase

c. Hepatic Lipase

d. Pancreatic Lipase

D

Which of the following conditions, besides pancreatitis and ulcers, is known to elevate lipase levels?

a. Hypothyroidism

b. Myocardial infarction

c. Muscular dystrophy

d. Intestinal obstruction

D

The extract from which plant seed is clinically useful for inhibiting the salivary isoenzyme of amylase?

a. Soy bean

b. Kidney bean

c. Corn kernel

d. Wheat germ

D

Which specimen handling error will specifically cause a false decrease in the measured activity of lipase?

a. Delay in centrifugation

b. Exposure to room light

c. Freezing the sample

d. Hemolysis

D

Alongside opiates and thiazide diuretics, which of the following cardiovascular drugs is noted to increase amylase measurements?

a. Amlodipine

b. Metoprolol

c. Digoxin

d. Methyldopa

D

The method that relies on monitoring the degradation of starch before and after the reaction is called the?

a. Saccharogenic method

b. Chromogenic method

c. Continuous Monitoring method

d. Amyloclastic method