B.3-digestion Flashcards
what are the two main roles of the digestive system
digestion- process of breaking down large food molecules into smaller molecules
absorption- process of absorbing small food molecules into the body
name all the organs that food passes through
-mouth
-oesophagus
-stomach
-small intestine
-large intestine
-rectum
-anus
the digestive system is an example of an organ system
what is an organ system
group of organs that work together to perform a certain function in an organism’s body.
the breakdown of food is catalysed by …
enzymes
what is the oesophagus
a muscular tube that carries food from the mouth to the stomach
3things the stomach does to aid digestion
-contracts muscular walls to churn and mix food
-produces pepsin, a type of protease and breaks proteins down into amino acids
-produces hydrochloric acid, killing microorganisms
name the muscular tube that carries food from the mouth to the stomach
oesophagus
where is bile made and stored
made by the liver
stored in the gallbladder
name 2 roles of bile
-to emulsify lipids
-to neutralise the acid from the stomach
state what enzyme breaks down carbohydrates
carbohydrase
-it breaks starch into sugars in the mouth and small intestine
-
state what enzyme breaks down proteins
protease
-foods such as meat, fish into amino acids
what are fats broken down into
fatty acids and glycerol
-in the small intestine
-LIPASE
what enzyme (s) does the pancreas produce
-carbohydrases
-proteases
-lipases
which enzyme does the stomach produce
proteases
state how the protease secreted in the stomach work efficiently
-by hydrochloric acid giving the stomach a low pH
2roles of the small intestine
-where most digestion takes place
-where nutrients are absorbed into the bloodstream
main role of large intestine
to reabsorb water
main role of rectum
to store FAECES until they’re ready to be released
4ways villis adapsted to its role
-many of them, large total surface area to absorb nutrients
-walls have single layer of cells
-good supply of blood
-cells lining the villi have microvilli on their surface
whats the main carb we eat
starch
what organs in the body produce lipase enzymes
small intestines and pancreas
which enzyme breaks down starch and what into
amylase
into maltose molecules
whats the role of the salivary glands
to proudce saliva
-moistens foods, so easier to swallow
-contains salivary amylase which digests starch into maltose
what organs in the body produce amylase
-salivary glands
-pancreas
-small intestine
