Question

Stool of a person containing whitish grey colour is due to malfunction of _________ organ.
A. Pancreas
B. Spleen
C. Kidney
D. Liver

Answer 1

Hint: Stool is the solidified digestive waste that is removed from the body by egestion on a daily basis. Changes in its color and texture might imply a diet change or malfunctioning of one of the digestive organs.

Complete answer:
- Pancreas is responsible for the secretion of pancreatic juice. Pancreatic juice contains inactive enzymes like trypsinogen, chymotrypsinogen, procarboxypeptidase, amylases, lipases, and nucleases. Trypsinogen is activated by an enzyme, enterokinase, secreted by the intestinal mucosa into active trypsin, which in turn activates the other enzymes in the pancreatic juice.
- Kidneys are a part of the excretory system and are responsible for urine formation. They filter blood through glomerular filtration, reabsorb ions, and molecules to maintain an equilibrium, and secrete ions in excess.
- Spleen is responsible for the formation of hematopoietic stem cells.
- Liver secretes bile salts and bile pigments. Breakdown of worn-out red blood cells gives rise to bilirubin, the primary pigment in bile. It is the end product from the degradation of the heme part of the hemoglobin. Hepatocytes take up bilirubin from the plasma, slightly modify the pigment to increase its solubility, and then actively excrete it into the bile. It is a yellow pigment that gives bile its color. Within the intestinal tract, this pigment is modified by bacterial enzymes, giving rise to the characteristic brown color of feces and urine. When bile secretion does not occur, as when the bile duct is completely obstructed by a gallstone, the feces are grayish-white.

Therefore, the correct answer is (D) Liver.

Note:
Another bile pigment disorder is known as Jaundice. In this, the bile pigments like bilirubin increase in the blood due to failure of their excretion. This causes yellowness in skin and eyes. Its cause can be the obstructed ducts of the liver.