Y1S2 011 III Biochem Liver Function Tests: chemical pathology and clinical biochemistry

What is the primary enzyme responsible for the degradation of bilirubin mono and di-glucuronides in the colon?

Beta-glucuronidase

What is the percentage of urobilinogen that is reabsorbed by the intestines and reaches the liver via the portal blood supply?

10%

Which of the following Organelles is NOT involved in the conjugation of bilirubin in the liver?

Mitochondria

What is the name of the protein that binds to bilirubin in the liver and helps to facilitate its excretion?

Ligandin Signup and view all the answers

What is the final product of the oxidation of urobilinogen in the large intestine?

Stercobilin Signup and view all the answers

What is the percentage of urobilinogen that is transported to the kidneys and oxidized to urobilin?

5% Signup and view all the answers

What is the primary function of ligandin in the hepatocyte?

To carry bilirubin from the cytosol into the smooth endoplasmic reticulum Signup and view all the answers

What is the primary difference between unconjugated and conjugated bilirubin in terms of solubility?

Unconjugated bilirubin is lipid-soluble, while conjugated bilirubin is water-soluble Signup and view all the answers

What is the rate-limiting step in bilirubin metabolism?

Secretion of conjugated bilirubin into the bile canaliculi Signup and view all the answers

What is the role of inorganic anions in the hepatic uptake of unconjugated bilirubin?

They are required for the facilitated diffusion of unconjugated bilirubin into the hepatocyte Signup and view all the answers

What is the enzyme responsible for the conjugation of bilirubin with glucuronic acid?

Uridine diphosphate glucuronosyltransferase Signup and view all the answers

In what form is bilirubin transported to the liver?

Unconjugated and bound to albumin Signup and view all the answers

What is the primary function of liver function tests?

To detect the presence of liver disease and monitor the response to therapy Signup and view all the answers

Which of the following enzymes is NOT a biomarker of liver injury?

Albumin Signup and view all the answers

In which type of disorders is there a proportionately greater increase in plasma AST activity than ALT?

Infiltrative disorders Signup and view all the answers

What is the primary advantage of liver function tests?

They are cheap, non-invasive, and widely available Signup and view all the answers

What is the primary source of AST released into serum in mild hepatocellular injury?

Cytoplasmic AST Signup and view all the answers

What is the typical relationship between AST and ALT in infiltrative diseases such as colon cancer that spreads to the liver?

AST > ALT Signup and view all the answers

Which of the following is a function of the liver?

Bilirubin production and metabolism Signup and view all the answers

What is the typical level of plasma ALP in obstructive cholestasis disease?

Greater than three times ULN Signup and view all the answers

Which of the following is NOT a characteristic of mild hepatocellular injury?

Nuclear fragmentation Signup and view all the answers

What is the significance of the liver's functional reserve?

It allows the liver to function normally even in the presence of severe disease Signup and view all the answers

What is the primary reason for mild cholestasis in hepatocellular diseases?

Obstruction of bile canaliculi by swollen hepatocytes Signup and view all the answers

What is the primary function of gamma-glutamyl transferase in the liver?

Transfer of gamma-glutamyl groups Signup and view all the answers

Which of the following is a true statement about liver function tests?

They are used to assess the severity and predict the outcome of liver disease Signup and view all the answers

What is the primary consequence of Wilson disease on the liver?

Copper buildup Signup and view all the answers

Which of the following is a non-pathological cause of elevated alkaline phosphatase levels?

Age greater than 60 years Signup and view all the answers

What is the typical sample used for liver function tests?

Blood sample Signup and view all the answers

What is the normal reference interval for gamma-glutamyl transferase in serum?

10-70 U/L Signup and view all the answers

Why is gamma-glutamyl transferase a more sensitive marker for cholestatic damage than alkaline phosphatase?

It is more specific to the liver Signup and view all the answers