organistation stuffs Flashcards
preparation of the food sample
get piece of food and break it up using pestle and mortar
transfer ground up food to a beaker and add distilled water
stir mixture w/ glass rood to dissolve some of food
filter solution w/ funnel lined w/ filter paper to get rid of solid parts of food
test 4 sugers
prepare food same and transfer 5cm^3 to test tube
prepare water bath at 75 degrees
add benedicts solution using pipette
place test tube in water bath using test tube holder and leave for 5 min. ensure tube is pointing away frm u
if turns from blue to red orange yellow green sugar present
test for starch
transfer 5cm^3 of food sample to test tube.
add iodine solution, gently shake tube
if goes from orange to blue/blaack, starch present
test 4 protein
prepare sample of food and trasnfer 2cm^3 of sample to test tube
add 2cm^3 biruet soluion to samle and mix contents of tube by gently shaking
if change from blue to purple, protein present
test for lipid
prepare sample of food. transfer 5cm^3 to test tube
add 3 drops of sudan 3 stain solution to test tube n gently shake
if lipis present two layers form, top layer bright red. if no lipid, no red layer forms
whats cancer
uncontrolled cell division
benign tumour
tumour grows until no more room. doesnt spread. doesnt invade other tissues in body.
malignant tumour
tumor grows and spreads to nearby healthy tissues
can also travel to other parts of body via bloodstream
they then invade tissues and form secondary tumours.
which tumour type is cancer
malignant
cancer risk factors
smoking
obesity
uv exposure
viral infection
genetics
adaptations of le guard cells
when plant has lots of water, guard cells go plump and turgid. stomata open so gases can be echanged for photosynthesis
when short of water, guard cell lose water and become flaccid and close to stop water vapour escaping
then outer walls and thick inner walls make opening and closing work
sensitive to light - close at light to save water without losing out on photosynthesis
kidney shaped to open and close stomata
more stomata on underside of leaf as its shaded and cooler so less water lost
stents avatage
effective for long time
recovery time from surgery is quick
lower risk of heart attack
stents disavantage
risk of complications during operation
risk of infection from surgery
risk of thrombosis - blood clot near the stent
statin avatage
reduce ldl cholesterol in blood
increase amount of hdl cholsterol
can also prevent some other diseases
easy to take
statin disvantge
must be taken regularly for the rest of your life. risk someone forgets
could cause engative side effects
not instant effect
artificial heart used for
use until donor heart can be found or help person recover by letting heart rest and heal
some cases permanent fix
avantage le artificiel heart
wont be rejected by body
disavantage heart de artificiales
surgey can lead to infection n bleeding
dont work as well as normal hearts
could wear out, electrical motor could fail
could cause blood clots leading to strokes
drugs needed to be taken to thin blood which can cause problems if they get injured
faulty heart valves
valves can be damaged by heart attack infection or old age
damage can cause valve tissue to stiffen so it wont open properly or it leaks and allows backflow of blood
where can replacement valves be soirced from
humans or other mammals e.g cows pigs
or can be mechanical valves
risk of artificla valve
blood clots
artificial bloooooood
is a blood substitute eg salt solution
used to replace lost volume of blood
rate blood flowww
volume of blood/ number of minutes
breating rateeee
number of breaths/number of mins
parts of le microscopie
stage - where microscope slide placed
clips - hold the slide in place
lamp - light from it passses through microscope slide
objective lenses - allow u to look at a magnified specimin
eyepiece - where u look through
eyepiece lens - has a magnification of 10x
microscope practicallllll
put slide on stage
use clips to hold slide in place
slsect lowest power objective lens
poisiton objective slide so it is alsmost touchning slide, to do this turn coarse focusing dial. then turn it again until cells come in focus.
then use fine focusng dial to bring cells to clear focus
increase magnification until can see clearly
effect of ph on amylase practical - preparation
place one drop of iodine into well of spotting tile
in one test tube put 2cm^3 starch solution, in other one put 2cm3 amylase solution, in other one put 2cm3 ph 5 buffer solution
effect of ph practical
place all three in water bath 30 degree 10 min for solutions to reach correct temps
then combine 3 solutions into 1 test tube and mix with stirring rod. return tube to waterbath and start stopwatch
after 30 sec add one drop of solution to well in spotting tile that has iodine - should turn blue/black
do this with each drop every 30sec until one drop makes iodine not change colour
record time taken until this happen
repeat experiment using different ph buffers
problems with expermient ph
taking sample every second - gives approx time. could sample every 10 sec instead
looking for time iodine doesnt turn blue black - hard to tell as there may be small bits of blue black - could ask multiple people to look and decide if finished
when plant cell in water what happensnsssss
water moves into cell and cell expands
what happen when plant cell in concentrated solution
water leaves cell causing it to shrink
first step osmosis prctical
peel potato as potato skin can affect osmosis
2n step osmosis practical
use cork borer to make 3 cylinders of potato. cylinders must have sae diameter
3rd step osmosis practical
use scalpel to trim cylinders to same length
4th step osmosis practical
measurelength and mass of cylinder
5th step osmosis practical
add 10cm3 of 0.5 molar sugar solution to a test tube
add 10cm3 of 0.25 molar sugar solution to second test tube
add 10cm3 of distilled water to third test tube
6th step osmosis practictal
leave potato cylinders overnight to allow osmosis to take place
why is distilled water used
doesnt contain dissolved sbstances which would affect rate of osmosis
