Biology · Ch 14 — Human Nutrition
Absorption in Different Regions of the Alimentary Canal
14.5.1
Absorption in Different Regions of the Alimentary Canal
Absorption occurs to differing degrees at each level of the alimentary canal:
- Mouth: absorption occurs through the mucosa of the mouth and the lower surface of the tongue into blood capillaries — for example, certain painkiller drugs are absorbed here.
- Stomach: the gastric mucosa is largely impermeable, so most nutrients pass through unabsorbed until they reach the small intestine. Only a little water, some electrolytes, alcohol and certain drugs (such as aspirin) are absorbed in the stomach. …
Table 14.5.1Absorption of Nutrients in Different Regions of the Alimentary Canal
Mouth: absorption through the mucosa of the mouth and lower surface of the tongue into blood capillaries, e.g. certain painkiller drugs.
Stomach: gastric mucosa is largely impermeable; little water, electrolytes, alcohol and drugs like aspirin are absorbed.
Small Intestine: glucose, fructose, galactose, amino acids, minerals and water-soluble vitamins absorbed into blood capillaries of the villi; lipids and fat-soluble vitamins (A, D, E, K) absorbed into the lacteals. …