Plants and their functions Flashcards
write the word and symbol equations for photosynthesis
water + carbon dioxide -> glucose + oxygen
H2O + CO2 -> C6H12O6 + O2
why does each food chain need to start with the green plant or algae
so that the green plant or algae can produce glucose from the suns energy and therefore biomass
which part of a plant cell absorbs light to allow photosynthesis to occur and what is the chemical called which is inside of this organelle
chloroplasts absorb the sunlight and the chlorophyll is the chemical inside of them
what type of reaction is photosynthesis and what does this mean
endothermic reaction as energy is taken in during the reaction
what are the three limiting factors of photosynthesis
light intensity, temperature and carbon dioxide concentration
what does a limiting factor mean
they can stop photosynthesis from happening any faster
describe what happens to the rate of photosynthesis if: a. light intensity increases, b. carbon dioxide concentration increases, c. temperature increases
a. photosynthesis gets faster as light intensity increases, b. photosynthesis gets faster as carbon dioxide concentration increases, c. photosynthesis gets faster as temperature increases but only until a certain temperature, if it is too hot it slows down and can stop
what is the limiting factor on a light intensity limiting factors graph when light intensity and rate of photosynthesis are no longer directly proportional
even carbon dioxide or temperature
how was your describe the relationship between light intensity and rate of photosynthesis, what about distance from the light source and rate of photosynthesis
light intensity is directly proportional to the rate of photosynthesis, distance from the light source is inversely portional to the rate of photosynthesis
how are root hair cells specialised for their job
they have a very large surface area to allow maximum absorption of water as each root hair cell is covered in millions of microscopic hairs
which process is water absorbed into plant roots, which process of mineral ions absorbed by
water is absorbed by osmosis while mineral ions are absorbed by active transport
are phloem and xylem cells dead or alive
phloem cells are alive while xylem cells are dead
what do phloem cells transport and how
phloem cells transport food substances, like sucrose, from the leaf, where it’s made, to the rest of the plant for use or storage, this is called translocation
what does xylem cells transport and how
they transport water and mineral ions from the root to the stems and the leaves, this movement is called the transpiration stream
describe the structure of phloem cells
columns of elongated cells with end walls containing small pores to allow substances to be transported through
describe the structure of xylem cells
tubular cell structure is made of dead cells with no end walls and a hole down the middle, they are strengthened with a material called lignin
through which two processes is water lost from the surface of the leaf in transpiration
evaporation and diffusion
why does transpiration cause the water to move up through a plant
The loss of water from the leaf causes of reduced concentration of water in the leaf some more water is drawn up through the xylem cells to replace it
what do we call the constant flow of water from the roots and up to the leaves
transpiration stream
what is also carried along in the transpiration stream apart from water
mineral ions
what do we call the tiny pores in the surface of a plant and where are most of these found
stomata found mostly on the underside of the surface of a leaf
what is the purpose of a stomata
they allow oxygen and carbon dioxide to enter and leave through diffusion, water vapour also escapes during transpiration
explain why water leaves the stomata by diffusion
water leaves the stomata as it goes from an area of high concentration inside the leaf to an area of low concentration outside
how do guard cells cause the stomata to open
guard cells surround the stomata, when the guard cells are full of water they change shape causing the stomata to open
how do guard cells cause the stomata to close
guard cells surround the stomata, when the guard cells are low in water they change shape causing the stoma to close
how does sucrose get transported around the plant
sucrose is translocated in the sieve tubes of phloem tissue, each sieve tube is connected to the neighbours by holes which sucrose flows through
which type of cells pump sucrose into sieve cells
companion cells
why does pumping sucrose into sieve cells cause sucrose to move
it increases the pressure of where it is pumped into causing the solution to flow up into growing shoots or down into storage organs
name three factors which affect the rate of transpiration
light intensity, temperature, humidity, air movement
explain why transpiration levels will be higher on a windy day
the wind removes water particles from the air surrounding the leaf so there is a lower concentration of water around the leaf
explain why higher temperatures will increase the rate of transpiration
particles will move around faster and therefore diffuse faster
explain why increased light intensity will increase the rate of transpiration
increased life intensity means increased levels of photosynthesis, this will mean stomata are open wider therefore more water can leave the leaf through transpiration
what is the equation for estimating transpiration rate using a potometer
distance moved by the bubble/ time taken
