Food Digestion Flashcards
What does the process of breaking down food involve?
Ingestion, digestion, absorption, assimilation and egestion
What do the villi do?
Increase the surface area available for digested food molecules in the small intestine
What is digestion?
The breakdown of large insoluble molecules to smaller soluble ones
What is the alimentary canal?
A muscular tube which runs from your mouth to your anus
How does food moves through your gut?
Waves of muscular contraction. This is called peristalsis.
What is the function of the stomach?
A muscular bag which contains gastric juice of hydrochloric acid and pepsin
What happens in the small intestines?
In the duodenum secretion from the pancreas and liver are received, it breaks down food using enzymes. Absorption takes place in the ilium to the blood via the villi. The ilium absorbs digested food.
What does the pancreas do?
Produces pancreatic juices containing, amylase, trypsin and lipase
Test for glucose
Benedict’s regent, will turn from light blue to brick red
Test for starch?
Iodine solution will turn from orange brown to blue blue
Test for protein?
Biuret reagent will turn from light blue to lilac
What is assimilation?
Food molecules distributed around the body
What is bile?
A yellow liquid stored in gall bladder, made in the liver which turns lipids into an emulsion of tiny droplets. It is also alkaline to neutralise the stomach acids.
Where does the cellulose and dead bacteria go?
The colon
Where is water absorbed out?
The colon
What are faeces?
Semi solid waste material stored in the rectum and ejected from the anus
What is the difference between excretions and egestion?
Egestion is the process of getting rid of unused waste materials Excretion is the removal of metabolic chemical waste
What are the breakdown products of carbohydrase?
Glucose
What are the breakdown products in protease?
Amino acids
What are the breakdown products of lipase?
Fatty acids and glycerol
What is absorption?
The products of digestion are absorbed into your bloodstream in the small intestine.
What is egestion?
Water, undigested food, enzymes, dead cells, bile pigments and mucus move through the large intestine. Water is removed. The remaining material is passed out of the anus as faeces.
How is the ileum adapted to absorb digested food?
The surface area is covered in vlili, which in turn are covered in microvilli. This increases the surface area. Small intestine is folded to increase surface area. Outer surface is just one cell thick. Each villus has a capillary so a good blood supply. Each villus has a lacteal to transport fatty acids and glycerol.
What does amylase do?
Turn starch to maltose.
What does maltase do?
Turn maltose to glucose.
What does pepsin/trypsin do?
Turn proteins to peptides.
What does peptidase to?
Turn peptides to amino acids.
What does bile do?
Neutralises stomach acid and emulsify fats
