B2 Organisation Flashcards
what is the circulatory system
transports oxygen nutrients and waste products in the blood
nervous system
co-ordinates all of the bodies activities
muscular skeletal system
provides support stability and movement
respiratory system
exchange of gasses
digestive system
to break down food molecules contains the stomach small intestine and the large intestine
nervous system
brain spinal cord and neurons
mouth
chews food in two different ways - chemical and mechanical
salivery glands
produces saliva to aid digestion
what happens in the oesophogus
food travels down into the stomach
small intestine
brakes down food and collects the nutrients
large intestine
unchewed food gets broken down
rectum
where your feces is stored
what happens in the mouth
your teeth chew the food and the salivery glands produce saliva (containing enzymes) to break down the food
what happens in the stomach
hydrochloric acid breaks down food even further. it is churned around by muscles so it becomes a liquid, protease is produced
what happens in the liver
bile is produced which breaks down fats and neutralises acids
what are the adaptations of the small intestine
there is a large surface area because of the villi which are the tiny hair like structures which absorb the nutrients and the enzymes protease and amaylase are produced
what happens in the large intestine
water is absorbed
what happens in the anus
defectation
what are carbohydrates
molecules that are made up of the elements carbon and hydrogen
what are protiens
molecules that are made up of the elements carbon hydrogen oxygen and nitrogen protiens are made up of long chains of amino acids
what are lipids
molecules that are made up of the elements carbon hydrogen and oxygen, lipids can be fats or oils
what is the food test for starch
grind sample
add iodine
positive result = blue/black
negative result = orange/brown
what is the food test for lipids
grind sample
mix with water
filter mixture
add ethanol
positive = cloudy white
negative = clear
what is the food test for sugar
grind sample
mix with water
funnel mixture
add bennedicts solution
positive = red/orange/yellow/green
negative=brown
what is the test for protein
grind sample
mix with water
funnel mixture
add biruet soloution and shake
positive = purple
negative = blue
what is a positive starch test result colour
blue/black
what is a positive fats test result colour
cloudy white
what is the positive result for protein colour
purple
what is the positive result colour sugar
red/orange//green
what is lipase
breaks down fatty acids and glycerol
what is protease
breaks down proteins and amino acids
what is amylase
breaks down starch and glucose
what is carbohydrase
breaks down carbohydrate and simple sugars
how does blood flow around the body
arterys carry blood through the heart to the organs of the body. blood returns to the heart in the veins the twp are linked by a capilary network
what are the different types blood vessels
the main types of blood vessels are arterys veins and capilary networks
why are valves important
the valves prevent backflow ensuring that blood flows in the right direction
why are double ciruclaroy systems important
a double circulatory system is important in warm blooded active animal such as human - makes a circulatory system more efficient
what is an enzyme
an enzyme is a catalist that increases the speed of a reaction without being changed or used up in a reaction. enzymes are all large protiens and all proteins and all proteins are made up of chains of amino acids.
what is the structure of an enzyme
every enzyme has an active site with a unique shape that fits onto the substance involved in a reaction. enzymes usually only place one specific reaction.
why do enzymes only catalyse one specific reaction
because in order for the enzyme to work the substrate has to fit into its active site. if the substrate e doesn’t match the enzymes active site then the reaction won’t be catalysed
how does temperature affect enzymes
at first a higher temperature increases the rate of the reaction
but if it gets too hot some of the bonds holding the enzyme together break. this changes the shape of the enzymes active site,so the substrate won’t fit anymore. the enzyme then becomes denatured
how does pH affect enzymes
if the pH is too high or too low then it interferes with the bonds holding the enzyme together. this changes the shape of the active site and causes the enzyme to denature. all enzymes have an optimum pH they work best at, it is often pH 7 but not always
what is the method for the practical of investigating enzymatic reactions
1) put a drop of iodine into every well of a spotting tile
2) place a Bunsen burner om a heat proof mat and a tripod and gauze over the Bunsen burner. put a beaker of water on top of the tripod and heat the water until 35 degrees. try to keep the temperature of the water constant throughout the experiment
3) use a syringe to add 1 cm3 of amylase solution and add 1 cm3 of a buffer solution with a pH of 5 to a boiling tube. using test tube holders put the tube into the beaker and wait for 5 minutes
4) next use a different syringe to add 5 cm3 of a starch solution to the boiling tube
5) immediately mix the contents of the boiling tube and start a stop clock
6) use continuous sampling to record how long it takes for the amylase to break down all of the starch. to do this use a dropping pipette to take a fresh sample from the boiling tube every 30 seconds and put a drop into a well. when the iodine solution remains and browny -orange starch is no longer present
7) repeat the whole experiment with buffer solutions of different pH values to see how pH affects the time taken for the starch to be broken down
how to calculate the rate of reaction for the practical of investigating enzymatic reactions
rate of reaction = 1000 / time
for example at pH 6 the time taken for amylase to break down all of the starch in a solution was 90 seconds. so the rate of reaction = 1000 / 90 = 11