What pigment causes the normal yellow color of urine?

Urochrome is the pigment responsible for the normal yellow color of urine. It is a result of the breakdown of hemoglobin from red blood cells. When hemoglobin is decomposed, it transforms into bilirubin and then further into urochrome, which is excreted in urine. The concentration of urochrome affects the shade of yellow; more concentrated urine typically appears darker due to higher levels of urochrome. This pigment is a normal component of urine and its presence is indicative of normal metabolism and kidney function. In contrast, hemoglobin and bilirubin would cause abnormal coloration or in some cases indicate pathological conditions, while cholesterol does not have a direct effect on urine color.