Final answer:
Gallstones that are 100% cholesterol cast a distinct clean shadow. Gallstones are solid particles formed when cholesterol accumulates in the gallbladder. A blocked bile duct can cause jaundice.
Step-by-step explanation:
Gallstones that are 100% cholesterol will cast a very distinct clean shadow. Gallstones are solid particles formed when a large amount of cholesterol accumulates in the gallbladder. These stones can block the bile duct, causing pain and jaundice. When a gallstone blocks the bile duct, the bile cannot be excreted, resulting in a backup of bilirubin in the liver, which leads to jaundice.