Digestion Flashcards
What are the two types of digestion?
chemical and physical
what is chemical digestion?
the break DOWN of large insoluble food molecules to small soluble molecules by enzymes for absorption into blood
what is physical digestion?
the break UP of food with use of teeth and muscle
what enzyme breaks down protein and where is it found?
protease, in the stomach
what are proteins broken into?
amino acids
what enzyme breaks down starch, where is it found and what is it made into?
amylase, found in the salivary glands in the mouth and is made into glucose
what enzyme breaks down lipids and what is it broken into?
lipase, fatty acids and glycerol
what are proteins used for?
repairs and growth in muscles and tendons
hormones eg insulin
antibodies and enzymes/catalysts
how do we test for proteins?
biuret reagent test - it starts blue and goes purple in the presence of proteins.
what are lipids used for?
cell membranes, energy, hormones
how do we test for lipids?
emulsion test
what is the test for glucose and what are the steps?
Benedict's test take 5ml of Benedict's reagent add 8 drops of carbohydrate solution boil over flame or in boiling water for 2 mins let solution cool down if glucose isn't present colour is blue if it is present colour is orange/red
what does bile break up?
fats
what is the function of the pancreas
makes enzymes for the small intestine
what is the function of the liver
makes bile
what is the function of the gall bladder
stores bile
what is the function of the small intestine
chemical digestion and absorption of soluble foods
what is the function of the large intestine
absorb water
what is the optimum pH for the mouth
8 - saliva is alkaline
what Is the optimum pH for stomach
1-2, it can destroy viruses/bacteria
what is the optimum pH of the small intestine
8-9
what order does food flow through the digestive system
mouth - oesophagus - stomach - small intestine - large intestine - rectum - anus
what is one reason the stomach contains acids
it provides optimum pH for the protease enzyme
how is the small intestine adapted to perform its function
large surface area for food storage and large blood supply to maintain concentration gradient of soluble food molecules, also has a thin wall of cells for shorter diffusion distance.
what is ingestion
taking food into the body
what is digestion
the breakdown of large insoluble food molecules to small soluble food molecules by enzymes for absorption into the blood
what is absorption
taking soluble products of digestion into the blood
what is assimilation
the processes by which soluble food molecules that have been absorbed into the blood are then used in the body
what is egestion
removal of indigestible material from the body
what is the contraction of muscles in the oesophagus allowing the movement of food along the digestive system
peristalsis
what does bile do
neutralise the stomach acid and emulsifies fats - break fats into tiny droplets
where is protease produced
stomach, small intestine, pancreas
where is amylase made
salivary glands, pancreas, small intestine
where are lipases made
pancreas, small intestine
which group of digestive enzymes does amylase belong to
carbohydrases
what are carbohydrates converted into
sugars
