The digestive system

The stages of digestion

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The organs in the digestive tract
The role of the digestive system The role of the digestive system The role of the digestive system The role of the digestive system The role of the digestive system The role of the digestive system The role of the digestive system Anatomy of the digestive tract Anatomy of the digestive tract The anatomy of the digestive tract The anatomy of the digestive tract The anatomy of the digestive tract The anatomy of the digestive tract The anatomy of the digestive tract The digestive glands The digestive glands The digestive glands The digestive glands The digestive glands The digestive glands The digestive glands The abdominal brain The abdominal brain The abdominal brain The abdominal brain The abdominal brain The abdominal brain The abdominal brain
The stages of digestion
Transforming food Transforming food Transforming food Transforming food Transforming food Transforming food Transforming food Mechanical and chemical transformation Mechanical and chemical transformation Mechanical and chemical transformation Mechanical and chemical transformation Mechanical and chemical transformation Mechanical and chemical transformation Mechanical and chemical transformation Digestion: from mouth to anus From the mouth to the anus From the mouth to the anus From the mouth to the anus The mouth The mouth The mouth The mouth The mouth The mouth The mouth The oesophagus The oesophagus The oesophagus The oesophagus The oesophagus The oesophagus The oesophagus The stomach The stomach The stomach The stomach The stomach The stomach The stomach The small intestine The small intestine The small intestine The small intestine The small intestine The small intestine The small intestine The large intestine The large intestine The large intestine The large intestine The large intestine Domestiquer et transformer la nature pour produire The large intestine The large intestine Intestinal flora Intestinal flora Intestinal flora Intestinal flora Intestinal flora Intestinal flora Intestinal flora
Historical representations of digestion
In the 2nd century In the 2nd century In the 2nd century In the 2nd century In the 2nd century In the 2nd century In the 2nd century In the 17th century In the 17th century In the 17th century In the 17th century In the 17th century In the 17th century In the 17th century From the 18th to the 20th century From the 18th to the 20th century From the 18th to the 20th century From the 18th to the 20th century From the 18th to the 20th century From the 18th to the 20th centuries From the 18th to the 20th century Today Today Today Today Today Today Today
Digestive phenomena
What is a digestive event? What is a digestive event? What is a digestive event? What is a digestive event? What is a digestive event? What is a digestive event? What is a digestive event? Food going down the wrong way Food going down the wrong way Food going down the wrong way Food going down the wrong way Food going down the wrong way Food going down the wrong way Food going down the wrong way Eructation Eructation Eructation Eructation Eructation Eructation Eructation Hiccups Hiccups Hiccups Hiccups Hiccups Hiccups Hiccups Stomach ache Stomach ache Stomach ache Stomach ache Stomach ache Stomach ache Stomach ache Vomiting Vomiting Vomiting Vomiting Vomiting Vomiting Vomiting Borborygmus Borborygmus Borborygmus Borborygmus Borborygmus Borborygmus Borborygmus Intestinal wind Intestinal wind Intestinal wind Intestinal wind Intestinal wind Intestinal wind Intestinal wind Diarrhoea Diarrhoea Diarrhoea Diarrhoea Diarrhoea Diarrhoea Diarrhoea Constipation Constipation Constipation Constipation Constipation Constipation Constipation

The stomach wall contains gastric glands secreting gastric juices. These juices are very acidic (hydrochloric acid) and they dissolve nutrients. They are made up of enzymes (pepsin and lipase) whose major task is to make nutrients water-soluble.

Mucus is a gel covering the stomach wall and protecting it against acidity. 

The stomach wall contracts and creates a mechanical movement called churning. These contractions allow the alimentary bolus to mix well with the gastric juices, helping it to break down.

By the time they exit the stomach, the food particles have been finely broken down and some of the complex nutrients have been solubilised. After several hours of churning, the alimentary bolus continues on its journey to the duodenum.

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The stomach

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THE GASTRIC GLANDS

The stomach has gastric glands integrated in its walls. These glands secrete highly acidic gastric juices that dissolve nutrients. Gastric juices contain hydrochloric acid, which acidifies food and destroys some of the bacteria in the stomach. They also contain many enzymes that trigger chemical reactions. To give you an example, pepsin breaks down proteins into small chains of amino acids called peptides.

There is also gastric lipase, whose main role is to attack complex lipids and transform them into simpler lipids.

A gel-like substance called mucus covers the stomach wall. This mucus protects the stomach against the acidity of gastric juices, otherwise it would digest itself! The burning feeling in your throat after vomiting is due to the acidity of gastric juices.

MIXING

The stomach wall can contract and this mechanical action is called mixing. These contractions ensure that the bolus of food is mixed thoroughly with the gastric juices.

The bolus of food is transformed in a semi-fluid mass called chyme. This is highly acidic and is where some of the complex nutrients are transformed into simpler ones. The content of the stomach is continuously emptied out into the duodenum. In certain cases, chyme can remain in the stomach for 3 or 4 hours.

GASTRIC GLANDS IN DIGESTIX

In DIGESTIX, the ‘gastric glands’ and ‘mixing’ are both digestive pieces associated with the stomach. Gastric glands have two targets in the game. They transform proteins into small chains of amino acids, and complex lipids into simpler lipids.

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