Transport in plants Flashcards
(19 cards)
how are root hair cells adapted to their function (3)
- mitochondria
- large surface area
- large perminant vacuole
what cell + process transports sugar up and down the plant?
phloem , translocation
what cell + process transports water ( and mineral ions ) up the plant?
xylem , transpiration
define transpiration
the loss of water from a plant
how does glucose travel through the plant?
- gets converted into sucrose
- translocation
- phloem cell
why do xylem cells have lignin
for strength and support
what are sugars used for in plants
-energy
can be stored or immediatly used
why do phloem cells have companion cells
to provide them with energy
why do phloem cells have small pore seive plates?
to allow sucrose/sugar through
what happens when stomata open?
guard cells go turgid
what happens when stomata close
guard cells go flacid
why are stomata closed at night? (2)
- photosynthesis does not occur
- to conserve water
why is stomata open during the day? (3)
- let oxygen out
- let carbon dioxide in
- let water vapour out
describe how the transpiration stream allows water to move through the plant
- water molecules pull the molecule below it everytime water diffuses out
- this creates a continuous , unbroken stream in the xylem
- more water diffuses through the roots
where in the leaf does liquid water evapourate into water vapour
spongy mesophyll layer
4 purposes of transpiration?
1) to transport mineral ions (dissolved) throughout the plant
2) to provide cells with water so they become turgid
3) provide cells with water for photosynthesis
4) to keep the leaves cool
what factors affect traspiration rate? (4)
- temperature (KE)
- light intensity (guard cells sensitive to light)
- humidity (low conc difference)
- air flow (high conc difference)
what type of reaction is photosynthesis
endothermic
why are photosynthetic organisms main producers
the glucose they produce is turned into biomass and the energy in biomass is passed throughout food chains
