Question

What role do bile/bile salts play in digestion?

1) They emulsify larger fat droplets.
2) They provide a cellular channel through which some carbohydrates may enter epithelial cells.
3) They provide energy required for secondary active transport.
4) They catalyze the breakdown of large strands of nucleic acid.
5) They break down large proteins into smaller ones.

Answer 1

Bile salts act as emulsifying agents for breaking down and improving the digestion and absorption of lipid molecules by converting them into tiny droplets, aiding the action of digestive enzymes, and forming micelles that help transport fatty acids and glycerides into epithelial cells.

Step-by-step explanation:

Bile salts play a crucial role in the digestion of fats. They work as emulsifying agents to break down large fat droplets into smaller ones, known as emulsification. Emulsification is important because it increases the surface area of the fats, making them more accessible to enzymes like pancreatic lipases, which break down lipids.

After the breakdown of fats by lipases into fatty acids and glycerides, these smaller molecules can enter intestinal epithelial cells. Bile salts enable the formation of micelles which transport these molecules within the intestinal lumen. This absorption process is efficiently facilitated by the emulsion created by bile salts, eventually leading to the formation of chylomicrons that enter the bloodstream.

Bile salts are recycled through the enterohepatic circulation, which means after contributing to fat digestion, they are reclaimed in the ileum, sent back to the liver, and re-secreted with bile, preserving this valuable digestive agent.