Nutrition and digestion Flashcards
Define digestion
When the food we eat is broken down into nutrients the body can use
Where does the digestive system begin and end
The mouth and the anus
After we swallow food where does the food travel
Oesophagus, stomach, small intestine, large intestine
What are the four steps of digestion
1) Food enters the mouth and is chewed
2) Digested food is absorbed into the bloodstream in the small intestine
3) Excess water is absorbed back into the body in the large intestine
4) Any undigested food is excreted
What does the liver produce?
Bile to help with the digestion of lipids
How does the pancreas help digestion?
Produced enzymes to speed digestive reactions
What are enzymes?
Biological catalysts which speed reactions within the body
What does amylase break down?
Starch into sugar
What does protease break down?
Proteins into amino acids
What does lipase break down?
Lipids into fatty acids glycerol
Where are carbohydrates broken down?
Mouth stomach and small intestine
What does saliva contain?
Amylase
Where are proteins broken down?
Stomach and small intestines
Where are lipids broken down?
Small intestine
where are digested foods absorbed?
Small intestine
How is the body adapted to absorb?
The body can only absorb small molecules into the bloodstream, the surface area of the small intestine is large and thin. The wall is one cell thick and covered with villi to give a large surface area
What is Egestion?
When excess water is absorbed into the large intestine, the undigested food left is stored in the rectum, this then leaves as faeces
