Digestive System Flashcards
(23 cards)
What is food made from?
Food is made from large molecules which cannot be absorbed into the blood
Where does food come from?
Plants or other animals
What is the digestive system?
organ system that has the function to take in food and make it available for the rest of the body
The undigested food is passed out of what?
Anus
What is ingestion?
Ingestion is act of taking food into mouth
What is chewing?
food breaking down into smaller pieces in the mouth and mixing with saliva
What does saliva contain?
mucus which helps moisten the food and enzymes which breaks down starch into simple sugar molecules
What are enzymes?
special substances (proteins) and biological catalysts that speed up chemical reactions, used for many chemical reactions
What is the enzyme in saliva called?
Enzyme in saliva is called amylase and starts to work on digesting food in mouth
What do incisor teeth have?
Incisor teeth have sharp edge for biting and located in front
What do molar teeth have?
Molar teeth have wide surface with cusps to crush food
Where does the food go after the mouth?
Oesophagus
Where does the food go after it has been swallowed?
Stomach
What is the average time for the food to stay in the stomach?
4 hours
What does the churning of the stomach help with?
Churning of stomach helps physical breakdown of food and mixing it with gastric juice produced by stomach walls
What is gastric juice?
Gastric juice is mainly hydrochloric acid – kills microorganisms in food
Where does the acid mush go from the stomach?
Small intestine
Name some features of the small intestine.
Massive surface area (about 300m squared)
On surface, there are villi which stick out like many fingers
Each villus has tiny projections (things that stick out) called microvilli
Name some features of the large intestine.
Area where most water is absorbed into blood
Faeces stored in last part of large intestine, removal is called egestion
Is egestion the same as excretion?
No
How does food travel down the oesophagus?
By peristalsis
What is peristalsis?
Peristalsis is a wave-like contraction of muscles that pushes the food through a passage.
What is bile?
Bile is a substance produced by the liver. It is not an enzyme but contains enzymes such as lipase, protease and amylase.
