food and digestion Flashcards
Fatty acids and glycerol are used
-For energy
-To build cell membranes
-To make hormones
amino acids
used for building cell components
Glucose
used to supply energy
breakdown of fat
Firstly, bile (released by the gall bladder) allows the fat to ‘mix’ with water by breaking the fat into smaller droplets and increases the surface area of fat droplets. This is called emulsification
Secondly, the digestive enzyme lipase breaks each fat molecule into the smaller glycerol and fatty acid molecules.
enzymes
Enzymes are biological catalysts and they catalyse most chemical reactions in cells such as respiration, photosynthesis and protein synthesis.
Enzymes are large protein molecules made from a unique sequence of coiled amino acids this gives the active site - the area that is attached to the substrate a very specific shape that fits the substrate exactly
COMPLIMENTARY
enzymes function
enzymes help to:
* break down large molecules into smaller ones
* build large molecules from smaller ones.
* Change one molecule into another molecule.
temperature effect on enzyme activity
glucose food test
Reagent - Benedict’s
Method - add Benedict’s with food into test tube, heat
initial colour – blue
positive result - brick red
starch food test
Reagent - iodine
Method - add iodine to food.
initial colour – yellow
positive result – blue/black
lipids food test
Reagent - ethanol
Method - mash food in distilled water and pour liquid into test tube, add ethanol, shake and add cold water
initial colour – colourless
positive result – white milky emulsiom
Carbohydrase
released in - Salivary glands, Pancreas, small intestine
function - breaks down carbohydrates into sugars e.g. starch into glucose
lipase
lipase
released in – pancreas, small intestine
function - breaks down liquids into fatty acids and glycerol
protease
released in – stomach, pancreas, small intestine
function - breaks down proteins into amino acids
Carbohydrates
for energy
fats (lipids)
for energy & making cell membranes