Transport in plants

what does the xylem transport

water and minerals

what does phloem transport

sugars and sucrose

describe the position of the xylem and phloem in the leaf

describe the position of the xylem and phloem in the stem

describe the position of the xylem and phloem in the root

root hair cell

describe the pathway of water through a plant

root hair cell→root cortex cells→xylem→mesophyll cells

how do you investigate the pathway of water through a plant

describe the process of transpiration

• water is lost through the stomata

• more water is drawn up to replace the lost water

what is the transpiration stream

the transpiration stream is the flow of water through a plant

define transpiration

the evaporation of water from the aerial parts of a plant on the surface of the mesophyll cells which is followed by diffusion of water vapour through the stomata

why is water lost from plants

• plants have large air spaces in them

• plants have stomata in the leaves which allows water to diffuse out of the plant

• plants have a large surface area for evaporation to occur

how do the interconnecting air spaces affect the water vapour loss

• the interconnecting air spaces between the mesophyll cells create a large internal surface area

• this increases the amount of water which can evaporate from the leaf

how does the shape and size of the stomata affect water loss

• a greater number of stomata leads to more evaporation of water vapour from the leaves, increasing rate of transpiration

• a larger size of stomata also leads to more evaporation and increases the rate of transpiration

explain the movement of water through a plant

• water evaporation from the leaves creating a negative pressure in the xylem (transpiration pull)

• water is drawn up the xylem in a column that is held together by cohesion

how does temperature affect the rate transpiration

as the temperature increasing, so does the transpiration rate

how does the wind speed affect the rate of transpiration

the faster the wind speed, the faster the water is moved away from the plant, creating a steeper gradient and increasing the transpiration rate

what causes wilting

a lack of water which means the plant cells are not turgid and so the plant is not supported

describe translocation

translocation is the movement of sugars and amino acids up or down the phloem from source to sink (with the use of energy)