plant transport Flashcards
what is the function of xylem
to transport water and mineral salts from the roots to leaves
what is the 4 types of cell in xylem
tracheid, xylem vessels, parenchyma and fibres
describe what the tracheid are/do/ have
they hv a smaller diameter than xylem vessels and pointed ends
they have pits to allow water to flow
they transport water in-between cells
describe what xylem vessels are/do/ have
long tubes that join end to end
lignin for strength and permeability
what does parenchyma and fibres do
parenchyma- store food
fibres- support
what are the adaptations of xylem vessels and tracheid
lignin- strength & prevents food entry
open ends to allow water flow
pit to allow mineral salt and water pass through
open ends join to form hollow tubes - water and mineral salt pass sideways
what is the function of phloem
to transport products of photosynthesis from leaf to storage and growing areas
what are the 4 types of cells in phloem
sieve tubes, companion cells, parenchyma and fibres
describe what sieve tubes are
they have no nucleus and are dead cells
long cells that join end to end with no lignin
sieve plate lets substances pass through
what is companion cells
have nucleus and help sieve tubes
produces mitochondria
provide protein and energy
describe root pressure
high concentration of ms in cell, active transport from soil to cell. lower wp in cell so osmosis. causes root pressure
adaptation of root
has root hair cells which is just elongated cytoplast to increase surface area
has root cap to protect root
describe the pathway of water
soil - root- root hari-cortex- cell -xylem - leaf
describe the pathway of water
soil - root- root hair-cortex- cell -xylem - leaf
compares villus and root hair
similarities
both use active transport
absorb nutrients
have structures to increase surface area
differences
root hair absorb water and ms but villus absorb amino acid
root use AT to get nutrients but villus use diffusion
root hair has cytoplasm, nucleus and vacuoles but villus has lacteal and vein
why is root pressure not enough to bring water up the stem
it is insufficient to over come forces of gravity