digestive system Flashcards
food is essential for _____
life
what is digestion?
the process of breaking down larger food molecules into molecules which are small enough for use of body cells
what are the 5 steps of the digestive process?
- ingestion
- movement of food
- digestion
- absorbtion
- defecation
what is ingestion in the digestive process?
easting, taking in food
what is movement in the digestive process?
the movement of food along the gastrointestinal tract
what are digestions in the digestive process?
chemical and mechanical processes involved in the breakdown of food
What is absorption in the digestive process?
the absorption of nutrients and energy into the cardiovascular and lymphatic systems to be redistributed to other cells
What is defecation in the digestive process?
Elimination of indigestible substances
What is chewing called?
mastication
Where is saliva produced and why?
in glands in the mouth to aid the breakdown of food into a small mass called a bolus
Where does the tongue direct the bolus?
to the back of the mouth
what does the epiglottis do?
moves to cover the windpipe to ensure the bolus goes down the oesophagus
What are peristaltic waves? what do they do?
Involuntary muscle contractions that move the bolus down the oesophagus into the stomach
what letter is the stomach shaped like?
J
what is the stomach located under?
the diaphragm and liver
what is the main function of the stomach?
breaking down food into chyme
what is chyme?
semi fluid pulp
Why does the stomach act as a storage area for food?
because we eat food quicker than the digestive system can break it down
how many litres of chyme can the stomach hold and for how long?
4 litres of chyme for 2-4 hours
what is the role of the submucosa in the stomach?
to protect the rest of the body from harmful acids
what is chemical digestion?
Chemical digestion is a biochemical process that uses enzymes and water to break down complex molecules
what does the liver produce in chemical digestion? what does it do?
bile, helps break down fat
what does the pancreas produce in chemical digestion, what does it do?
digestive enzymes that help break down food further into really small molecules for absorption
What does the stomach lining produce? (1) what does this do? (2)
mucus, protects from acid, lubricates stomach,
different _________ break down different ________.
enzymes
foods
What are the 3 sections of the small intestine?
duodenum
jejunum
ileum
how long is the small intestine?
6m long
what is the longest and most convoluted part of the alimentary canal?
the small intestine