Digestive System: Food Digestion and Nutrient Absorption
Introduction (the digestion)
It is through eating food that our body removes the nutrients needed to build new tissues and also maintains damaged tissues.
This process is only possible thanks to the digestive system, which is responsible for transforming the food we eat into molecules small enough to penetrate our cells.
Human digestive system organs
This system responsible for both digestion and absorption of food is formed by the mouth, esophagus, liver, gallbladder, stomach, rectum (large and small) and attached glands.
Digestion begins in the mouth where food is ground by teeth and moistened by saliva. The taste of food is determined by the taste buds (located on the tongue), it is through them that we identify when a particular food is sweet, salty, sour or bitter.
Then the food bolus follows the pharynx that pushes it into the esophagus, which, through its peristaltic movements, pushes the food into the stomach.
In the stomach food is dissolved by the gastric juice, which is produced by stimulating factors such as sight, taste, odor, chewing, hunger, etc. Only 5% of digestion occurs in the stomach.
From the stomach, the bolus goes to the small intestine, where nutrients will be reduced to very small molecules through the digestion process.
The water in digestion
To carry out this process, the body uses on average ten liters of water. It is through the large intestine that most of this water is reabsorbed, only a small part of it is used to help the faecal sliding.
Main diseases and disorders affecting the human digestive system:
- Peptic ulcer, stomach cancer, bowel cancer, pancreatitis, gastritis, gastroenteritis and stomatitis.