Digestive System Flashcards
Essential Nutrients
Stages of Digestion
Mouth
Oesophagus
Stomach
Accessory Organs
Small Intestine
Large Intestine
Digestive Enzymes
Villi
- Small finger-like projections that increase the surface area of the small intestine
- Villi, is coated with a fluid containing digestive enxymes, epithelial cells have tiny projections called microvilli.
- Villi has rich blood supply, nutrients diffuse from small intestine into blood, villi has thickness of one epithelial cell, small difussion path increases rate of nutrients moving into blood. Blood vessels inside villi carry nutrients away from small intestine
- Concentration gradient is maintained by blood moving away from small intestine.
Duodenum
The first part of the small intestine. It connects to the stomach. The duodenum helps to further digest food coming from the stomach. It absorbs nutrients (vitamins, minerals, carbohydrates, fats, proteins) and water from food so they can be used by the body.
How enzymes break down nutrients
Enzyme concentration: Increasing enzyme concentration will speed up the reaction, as long as there is substrate available to bind to. Once all of the substrate is bound, the reaction will no longer speed up, since there will be nothing for additional enzymes to bind to.
Chemical v Mechanical Digestion
Coeliac Disease
Villi increase the surface area of your gut and help it to digest food more effectively. However, in coeliac disease, the damage and inflammation to the lining of the gut flattens the villi, reducing their ability to help with digestion.