Chapter 5 - The Digestive System And Enzymes Flashcards
What is digestion?
Digestion is the breakdown of large insoluble food molecules into smaller soluble food molecules
What are the two types of digestion
- phyical
- chemical
What is an enzyme?
An enzyme is a biological catalyst
What is a catalyst?
A substance that speeds up the rate of a chemical reaction without being used up in the reaction
What is amylase and whats its function?
Amylase is a digestive enzyme
Function : breaks starch down into maltose
What is the substrate?
The substance on which the enzyme acts is the substrate
What is the product?
The substance formed as a result of the reaction is the product
What are the stages in nutrition?
1) Eating : the food is taken into the mouth
2) digestion : the food is broken into smaller soluble molecules
3) absorption : the digested food is taken back into the bloodstream
4) getting rid of undigested waste as faeces
What happens in the mouth?
- the enzymes in saliva begin to chemically break down the food
- the teeth physical break down the food
What happens in the oesophagus?
-The food is ‘shunted’ down into the stomach through muscular contractions in the wall
What happens in the stomach?
- the stomach produces enzymes and other digestive juices
- the stomach muscle churns and mixes the food
- hydrochloric acid produced by the stomach kills bacteria and germs
What happens in the small intestine?
- digested food passes into the bloodstream (absorption)
- undigested wastes pass into the large intestine
Whats the function of the liver?
Produces bile to digest fats
Whats the function of the pancreas?
Produces enzymes
What happens in the large intestine?
- Take back water into the bloodstream
- the remaining material (Faeces) are stored in the rectum and released from the body through the anus
