photosynthesis and the leaf structure Flashcards
(28 cards)
is photosynthesis and endothermic or exothermic reaction
endothermic
what is an endothermic reaction?
a chemical or physical process that absorbs heat from its surroundings
what does light do in photosynthesis?
transfers energy to chlorophyll to enable photosynthesis.
what are chloroplasts
a plastid in green plant cells which contains chlorophyll and where photosynthesis takes place.
what are palisade cells?
neatly structures, full of normal plant cells, but have lots of chloroplasts.
what do chloroplasts have lots of
chlorophyll
what is the word equation for photosynthesis
water + carbon dioxide -> glucose + oxygen
how does oxygen get out of the leaf?
Oxygen can diffuse out of the spongy mesophyll or the stoma.
what are guard cells?
control what goes in and out of the plant. Mainly to let water out (or in), but can also let carbon dioxide and oxygen through.
what does photosynthesis do?
convert light energy into chemical energy in the form of glucose, essentially making their own food.
what do glucose molecules form ? and what does it break down to
a polymer called starch, this breaks down into sucrose
is glucose soluble or insoluble
soluble
does insoluble starch affect the water balance ?
no
where can starch be stored
roots, leaves and stems.
what is the starch energy store used for?
at night, when photosynthesis isn’t happening.
what are three limiting factors of photosynthesis?
temperature
light intensity
carbon dioxide concentration
Explain the inverse square law in
relation to photosynthesis
as a plant moves further away from a light source, the amount of light energy reaching its leaves gets less, and therefore the rate of photosynthesis decreases proportionately to the square of the distance
by increasing the light intensity…
the rate of photosynthesis increases
what is the control variable in the pondweed practical?
the piece of pondweed you use, temperature, carbon dioxide
what is the independent variable in the pondweed practical?
light intensity is changed
what is the dependent variable in the pondweed practical?
rate of photosynthesis is measured
what does it mean when a graph level is off
the rate of change in the data represented by the graph stops increasing or decreasing and becomes stable or constant
what is the palisade mesophyll and what is its structure
second layer of plant. has lots of chloroplasts, meaning it can carry out photosynthesis
what is the xylem and where is it found
found in the roots stems and leaves. a continuous tube made up of dead cells.
