Final answer:
Direct (conjugated) bilirubin is a type of bilirubin that is produced in the liver and excreted in the bile. It can be measured using the Van Den Bergh test and is used to diagnose and differentiate between different types of jaundice.
Step-by-step explanation:
Direct (conjugated) bilirubin is a type of bilirubin that is produced in the liver and excreted in the bile. It is formed when unconjugated bilirubin, which is a waste product of the breakdown of red blood cells, is processed by the liver and converted into a water-soluble form. Direct bilirubin can be measured using the Van Den Bergh test, which involves reacting it with a diazo reagent to produce a purple-red color. This test is used to diagnose and differentiate between different types of jaundice.