Final answer:
Feces get their normal color from stercobilin, which is the final product of the transformation of bilirubin in the intestines by bacteria.
Step-by-step explanation:
The substance that gives feces its normal color is stercobilin. When the spleen processes old or damaged red blood cells, it produces a waste product called bilirubin. Bilirubin is then transported to the liver and secreted into the bile. In the intestines, it is transformed by bacteria into urobilinogen and eventually into stercobilin, which provides the characteristic brown color of feces. Broad-spectrum antibiotics can disrupt these bacteria and may alter fecal color. Meanwhile, substances such as urobilins, which are related metabolic byproducts, are removed by the kidneys and secreted into the urine, contributing to its typical yellow color due to a pigment called urochrome.
The normal color of feces is brown, and this color is mainly due to the presence of urobilinogen. Urobilinogen is a product formed from the breakdown of bilirubin in the intestines by bacteria. Bilirubin is a waste product produced during the breakdown of hemoglobin in red blood cells. It is excreted in bile and eventually converted to urobilinogen, which gives feces its characteristic brown color