plants and their structures Flashcards
what is the equation for photosynthesis (word and symbol)
carbon dioxide + water —–> oxygen + glucose
6CO 2 + 6H 2 0 —–> C 6 H 12 0 6 —> 6O2
Explain why the products of photosynthesis have more energy than the reactants
since the energy enters from the surroundings , the products of photosynthesis have more energy than the reactants (endothermic reaction)
what products of photosynthesis is needed to make starch
glucose molecules
At what time of day would the starch in chloroplast be at its highest ? and why?
when there is light. This is because the plant stores the starch during the day for it to break up at night
explain how stomata open when it is light and close when it is dark
the stomata uses specialised cells called guard cells . in the light the water flows into the pair of guard cells making them rigid. At the night water flows out of the guard cells. they lose their rigidity and the stomata closes
what are the structures inside a plant?
cuticle - waxy coat
upper epidermis - contains tightly packed cells
palisade cells- packed with chloroplast. allows cell to absorb a great deal of light
air spaces - to provide large surface area for the plants to exchange gases with the air
lower epidermis contains stomata . diffusion of water CO2 and oxygen occurs her
explain why temperature is a limiting factor for photosynthesis
if the temperature is high - the rate of photosynthesis will increase because the enzymes used for photosynthesis will work faster. and vice versa but too high temperature causes enzymes too denature
explain the effect light intensity has on photosynthesis
if light intensity is high, the rate of photosynthesis will also be high
the rate of reaction levels off since another factor is limited and increasing the light intensity will have no effect.
what effect does concentration of CO2 have on the rate of photosynthesis.
when the concentration of CO2 increase rate of photosynthesis will also increase.the rate of reaction levels off since another factor is limited and increasing the concentration of CO2 will have no effect.
what is inverse square law
it calculates new light intensity when the distance of a light source changes.
I new = (I org * d org ^2) / d new ^ 2
how does plants lose water
carrying dissolved mineral ions
keeping cells rigid
cooling the leaves(evaporation)
photosynthesis
what are two ways in which roots are adapted to absorb a lot of water.
the roots have multiple hair-like structures , this provides a larger surface area so that water and mineral ions can be quickly absorbed
The hair also have thin cell walls so that the flow of water doesn’t slow down
what processes does water use to enter the plant
DIFFUSION - water enters the root and diffuses through the cell walls
OSMOSIS - water enters and the tiny tubes join the cytoplasm of some cells together allowing water to diffuse.
ACTIVE TRANSPORT - proteins in the cell pump ions into the cells
what happens during transpiration?
the flow of water into the roots up the stem and out of the leaves
what happens during translocation
the transport of sugars and the other compounds in the phloem tissue of a plant
