plant nutrition 🎀 Flashcards
what does photosynthesis produce for a plant?
‘food’ so it can survive
what energy does photosynthesis convert?
light energy to chemical energy
word equation for photosynthesis?
carbon dioxide + water - glucose + oxygen
balanced chemical equation for photosynthesis?
6CO2 + 6H2O - C6H12O6 + 6O2
TESTING A LEAF FOR STARCH: why do you boil the leaf for 2 mins in water?
kills the leaf and stops it photosynthesising
TESTING A LEAF FOR STARCH: why do you turn the bunsen burner off?
ethanol is flammable
TESTING A LEAF FOR STARCH: why do you heat the leaf in ethanol?
removes the green colour (chlorophyll) from leaf
TESTING A LEAF FOR STARCH: why do you rinse the leaf in warm water?
softens leaf
TESTING A LEAF FOR STARCH: why do you add iodine to the leaf?
see if leaf contains starch
why is light needed for photosynthesis?
- cover part of leaf with aluminium foil and leave in sunlight.
- covered parts will be negative for starch (orange/brown)
- uncovered parts will be positive for starch (blue/black)
why is chlorophyll needed for photosynthesis?
- variegated leaves show this.
- white parts go orange/brown when tested with iodine
- green parts (containing chlorophyll) turn blue/black
why is carbon dioxide needed for photosynthesis?
- place plant in beaker of sodium hydroxide (which will absorb CO2 from air)
- place another plant in beaker of water (which will not absorb CO2 from air)
what does the magnesium ion do?
make chlorophyll
what happens to the plant without magnesium ions?
yellow leaves due to less chlorophyll being produced
what does the nitrate ion do?
combine with glucose to make amino acids (proteins) for growth.
what happens to the plant without nitrate ions?
stunted/less growth due to less protein produced.
as light intensity increases…
the rate of respiration INCREASES up to a MAXIMUM where it LEVELS OFF.
(even at high light intensity, another factor limits the rate).
as co2 concentration increases…
the rate of respiration INCREASES up to a MAXIMUM where it LEVELS OFF.
(even at high co2 concentration, another factor limits the rate).
as temperature increases…
the rate of respiration INCREASES up to a MAXIMUM where it DECREASES.
(at high temperatures the enzymes denature).
STRUCTURE OF LEAF -
how is the waxy cuticle adapted for photosynthesis
waterproof layer - prevents water loss
LEARN HOW TO LABEL DIAGRAM FOR LEAF PARTS
A* GIRLIEEE
STRUCTURE OF LEAF -
how is the upper epidermis adapted for photosynthesis
transparent - maximises sunlight passing through
STRUCTURE OF LEAF -
how is the palisade mesophyll adapted for photosynthesis
lots of chloroplasts near top of leaf - long and thin to increase S.A. for max light absorption.
STRUCTURE OF LEAF -
how is the spongy mesophyll adapted for photosynthesis
air spaces - increase S.A. for movement of gases in and out of leaf. close to stomata.
STRUCTURE OF LEAF -
how is the xylem adapted for photosynthesis
supplies water to leaf from roots
STRUCTURE OF LEAF -
how is the lower epidermis/guard cells adapted for photosynthesis
many stomata allow CO2 to move in and O2 and water vapour out by diffusiom.
EVOLUTION OF O2 FROM ELODEA
what was dependent variable?
count the number of O2 bubbles produced per minute to measure rate of photosynthesis.
EVOLUTION OF O2 FROM ELODEA
what was independent variable?
change distance of light from plant to change light intensity.
EVOLUTION OF O2 FROM ELODEA
what was control variable?
amount of CO2 or temperature.
