Question

Chief function of bile is
A. To digest fat by enzymatic action
B. To emulsify fat for digestion
C. To eliminate waste product
D. To regulate process of digestion

Answer 1

Hint: Bile is secreted by hepatic cells (liver) and is stored in the gallbladder. It helps in the emulsification of fats. It means breaking down the fats into very small micelles. Bile juice activates lipase enzyme and further lipase acts on fats and breaks down fats into diglycerides and monoglycerides and family into glycerol and fatty acids.

Complete Answer:
- Bile is produced and the life is later stored in the liver. When food enters into duodenum the stored bile from gallbladder is released into the duodenum via bile duct.
- Enzymes play an important role in the digestion of food. Specific enzyme acts on a particular food substrate and breaks it down to simpler substances. Among the seven components of food fats take longer to digest since these are complex molecules and need to be alcohol soluble. Lipase enzyme can act on fats but since the fat molecule is bigger therefore lipase cannot directly act on it.
- Bile has a major role to play in the digestion of fats. Bile emulsifies (breaks fats into smaller parts) the fats. The emulsification will increase the surface area for the enzyme lipase to act. - The increased surface area leads to a faster rate of reaction. Digestion of fats starts in small intestine and ends in small intestine just because of bile activity on fats
- Elimination of waste products takes place through various organs such as lungs, kidneys, liver and skin.
- Digestion process involves various enzymes and enzymes need suitable conditions such as pH and temp to work. The regulation of digestion is accompanied by the activity of enzymes.

The correct answer is “B” To emulsify fat for digestion.

Note: Bile contains water, bile salts. (Sodium Chloride, Sodium Bicarbonate and Sodium Glycocholate and Sodium Taurocholate), bile pigments (bilirubin and biliverdin), fatty acids, cholesterol and lecithin, but it has no enzymes.