plants Flashcards
what is osmosis
when water moves to an area of higher solute concentration through a semi-permeable barrier
hypotonic
when a solution has a lower solute concentration than another solution
hypertonic
when a solution has a higher solute concentration than another solution
isotonic
when a solution has the same solute concentration than another solution
what is the WORD equation of photosynthesis
carbon dioxide + water -> glucose + oxygen
what is the balanced equation for photosynthesis
6CO2 + 6H2O -> C6 H12 O6 + 6O2
how is a leaf adapted for photosynthesis
-high sf area to vol ratio
-thin leaf blade allows light to penetrate to leaves below
-lots of chloroplasts with chlorophyll
-stomata on underside to allow CO2 in
what is the top mesophyll of a leaf called
palisade mesophyll
what is the bottom mesophyll of the leaf called
spongy mesophyll
full of air pockets allowing for more CO2 to be absorbed
what happens to excess glucose made by the plant?
It is converted into a carbohydrate called starch
At night, starch is broken down back into glucose to be used for respiration
how to test for starch in a leaf?
- place leaf in boiling water to remove waxy cuticle
- place the leaf into a boiling tube of ethanol
- place the boiling tube into a beaker of hot water to remove the green colour
- after 5 minutes, remove the leaf and rinse it in hot water
- put the leaf on a white tile and cover with iodine
how does iodine react to starch?
it goes from an orange to blue/black colour
word equation of respiration
glucose + oxygen -> carbon dioxide + water
what is a limiting factor?
a factor that slows down the rate of reaction if there is not enough of it
what are the 3 limiting factors of photosynthesis?
-light intensity
-availability of carbon dioxide
-temperature
why would a very high temperature slow the rate of photosynthesis
it would denature the enzymes in the plant, preventing the formation of enzyme-substrate complexes
how to make algal balls
- use a pipette to place algae into a bijou bottle (plastic w lid)
- use a pipette to place sodium alginate into the bijou bottle
- tip bijou bottle back and forth to mix
- fill a beaker with 50ml calcium chloride
- pour bijou bottle into a syringe
- place syringe above beaker of CaCl and let algae drip into beaker
- rinse balls in distilled water
what is dependent variable?
variable which changes based on other factors
what is independent variable?
variable we change
light intensity practical with algal balls:
- place rinsed algal balls in bijou bottles
- ensure every bottle has equal no of balls
- fill each bottle with indicator solution
- place bottles at diff distances from lamp (shown by 30cm ruler)
- after time, record pH colour
-CO2 is acidic - PURPLE: CO2 removed=closer to lamp
-YELLOW: CO2 added=further from lamp
cell wall
support cell structure
prevents lysis when absorbing water
freely permeable
