Question

Absorption of digested food chiefly occurs in
(a) Stomach
(b) Colon
(c) Small intestine
(d) Large intestine

Answer 1

Hint: Absorption is the uptake of water, minerals, vitamins, and the end product of the digestion of carbohydrates, proteins, lipids, and nucleic acids to the body fluids. Digestion and absorption take place in the same area in intracellular digestion. In extracellular digestion, absorption is restricted to some localized areas.

Complete step by step answer:
In vertebrates absorption occurs mostly in the small intestine, although some absorption occurs in the stomach and large intestine also. The absorptive cells of the lining of the alimentary canal have two main features; .they have numerous mitochondria, ER, and Golgi bodies, they are brush bordered with fine microvilli at their end. Microvilli increase the surface area for absorption. Absorption involves three major mechanisms, namely passive absorption, active absorption, and Hulk transfer. Passive absorption is the energy-independent transport of substances in concentration and electrochemical gradient. Active absorption is the energy-dependent and carrier- mediated transport of substances across plasma-membranes.

Additional Information:
- Bulk transfer is the absorption of substances in large bulk by endocytosis.
- Absorption of sugars occurs mostly by active transport.
- proteins are absorbed mainly as amino acids.
So, the correct answer is 'Small intestine'.

Note:
- The uptake of lipids and products of their breakdown intestinal epithelial cells is by passive diffusion across the plasma membrane.
- Absorption of vitamins occurs in the anterior part of the small intestine.
- Electrolytes are absorbed from the lumen of the small intestine.