Studied by 1 person
Looks like no one added any tags here yet for you.
what elements do carbohydrates contain
carbon
hydrogen
oxygen
what elements do proteins contain
carbon
hydrogen
oxygen
nitrogen
what elements do lipids contain
carbon
hydrogen
oxygen
what are proteins made out of
long chains of amino acids
what are carbohydrates made up of
simple sugars
what are large, complex carbohydrates made out of
many smaller units joined together in a long chain
what are examples of smaller units of carbohydrates
glucose
maltose
what are examples of large, complex carbohydrates
starch
glycogen
what are lipids made out of
fatty acids and glycerol
how to prepare a food sample
break of a piece of food using pestle and mortar
add distilled water
mix
filter the solution
use the filtrate
how to test for glucose
prepare food sample
prepare water bath at 75c
add benedict solution
leave it there for 5 minutes
what happens if glucose is present
changes from blue to green to yellow to brick red
depending on concentration
how to test for starch
prepare food sample
add iodine solution
shake
what happens if starch is present
changes from brown-orange to blue-black
how to test for proteins
prepare food sample
add biuret solution
shake
what happens if proteins are present
changes from blue to pink to purple
how to test for lipids
prepare food sample without filtering
add Sudan III stain solution
gently shake
what happens if lipids are present
mixture will separate into two layers
top layer will be bright red - staining the lipids
balanced diet definition
provides the essential nutrients we need
in the right proportions
what is the function of carbohydrates
provides energy
what is the function of lipids
provides energy
provides insulation
acts as energy store
what is the function of proteins
growth and repair of tissue
provides energy in emergencies
what is the function of vitamin a
improves vision
keeps skin and hair healthy
what is the function of vitamin c
prevents scurvy
what is the function of vitamin d
needed for calcium absorption
what is the function of calcium
makes bones and teeth
what is the function of iron
makes haemoglobin for healthy blood
what is the function of water
need a constant supply of water for every bodily function
what is the function of dietary fibre
aids movement of food through the gut
what happens if there isnt enough dietary fibre
constipation
what are carbohydrates found in
pasta
rice
sugar
what are lipids found in
butter
oily fish
what are proteins found in
meat
fish
what is vitamin a found in
liver
carrots
what is vitamin c found in
fruits
what is vitamin d found in
eggs
what is calcium found in
milk
cheese
what is iron found in
red meat
what is dietary fibre found in
fruit
wholemeal bread
what does energy requirement depend on
age
activity level
pregnancy
why do pregnant women need for energy
support fetal growth and development
what happens if there is a deficiency of iron
causes anaemia
leading to fatigue and weakness due to lack of oxygen transport
what happens if there is a deficiency of vitamin d
causes rickets
small weak bones for children
what does starch, proteins and fats have in common
large molecules
insoluble
what does amylase do
converts starch into maltose
what does maltase do
converts maltose into glucose
what do proteases do
converts proteins into amino acids
what do lipases do
converts lipids into glycerol and fatty acids
where is amylase found
salivary glands
pancreas
where is protease found
stomach
pancreas
small intestine
where is lipase found
pancreas
mouth
stomach
functions of bile
neutralizes stomach acid
emulsifies fat
function of hydrochloric acid in stomach
kills bacteria
creates acidic environment for pepsin
why does bile neutralize stomach acid
to make sure the pH is optimum for enzymes to work in
emulsification definition
breaks down fat into tiny droplets
gives it a bigger surface area for lipase to work with
digestion is faster
where is bile produced
liver
where is bile stored
gall bladder
where is bile released
small intestine
peristalsis
series of wave-like muscle contractions that move food through the digestive track
what is the function of the mouth
salivary glands produce amylase in saliva
teeth mechanically break down food
difference between mechanical and chemical breakdown of food
mechanical digestion involves physically breaking down foo (via chewing or stomach churning)
chemical digestion involves enzymes and bile
what is the function of the oesophagus
muscular tube connecting mouth and stomach
what is the function of the stomach
pummels food with its muscular walls
produces the protease enzyme pepsin
produces hydrochloric acid
what is the function of hydrochloric acid
kill bacteria
give optimum pH for protease enzyme to work (acidic)
what is the function of the pancreas
produces protease, amylase and lipase
releases them into small intestine
what is the function of the small intestine
produces protease, amylase and lipase enzymes to complete digestion
nutrients are absorbed here
what is the first part of the small intestine called
duodenum
what is the last part of the small intestine called
ileum
what is the function of the large intestine
excess water is absorbed from the food
what is the function of the rectum
faeces are stored before excreted through the anus
assimilation
process where absorbed nurtients are used to build new tissues and cells
adaptions of villi
single permeable layer
good blood supply
long
microvilli
what does a good blood supply and single-permeable layer help with villi
assists in quick absorption
small distance for diffusion
what does microvilli and being long help with villi
there is a large surface area
more diffusion into bloodstream
roles of lacteals in villi
absorb fatty acids and glycerol into the lymphatic system
how is glucose absorbed from the small intenstine to the bloodstream
via active transport
