Vascular plant systems Flashcards
(24 cards)
Root pressure
root hairs, high SA, absorb H20 and minerals from soil
Water absorbed by osmosis
dissolved ions absorbed by process of diffusion
Force of H20 entering root and “pushing” its way into cells create pressure.
How Capillary action occurs
Adhesion
Cohesion
Transpiration stream
Adhesion
Force of attraction between water and Xylem
Cohesion
Force of attraction between H2O molecules help to pull molecules up narrow Xylem vessel
Transpiration stream
Continuous column of water through plant
capillary action
Combination of Adhesion and Cohesion forces allows water to flow in narrow spaces in opposition to gravitational forces
capillary action necessary for water to be transported up plant stems in a transpiration stream.
Transpiration
loss of water vapour by evaporation from the surface of a plant, especially via stomata
When stomata open, continuous stream of H2O rises through the plant
Environmental factors affecting transpiration: light, Humidity, Wind, Temp.
Translocation
transportation of photosynthesis products and some minerals
Active movement of soluble sugars through the phloem of vascular plants from a source to a sink.
can occur in any direction, depends on need of plant.
Sugars transported against concentration gradient into sieve cells.
Requires energy, energy comes from cellular respiration.
non-vascular
No roots but have leaves
vascular plants
Contain vascular tissue
adaptation
Change in characteristics of an organism that makes it better able to survive its environment
physiological, process or function
Structural, physical
plant adaptations in arid land
Stomata location
Thick waxy cuticle
lignen reinforced tissues
Altered root system
storing carbon for later
Leaf size
colour
Rhizone (root stalk)
Shoot system
comprised of: leaves, stem, flowers, seeds
Responsible for: transportation of resources, absorption of O2 and CO2, reproduction and carrying out photosynthesis in leaves
root system
Below ground
responsible for: absorption of H2O and nutrients from soil
H2O moves into roots through Osmosis
Nutrients in form of ions enter via diffusion of active transport
Xylem
Responsible for transport of H2O along with minerals and nutrients needed for growth and other processes.
roots to leaves in one direction.
H2O absorbed through root system in root hairs
Tubular, elongated cells that allow water to pass freely
When xylem cells mature, they die, hollow cells supported by cell walls remain, suited for H2O transport, dead tissue forms woody part of stems
Phloem
Transports sugars and other photosynthesis products from one part of a plant to where they are needed
Either direction
consists of conductive tissue composed of thin walled cells
Phloem is inner-most part of bark
Function: gases exchanged at stomata and plant surface, phloem distributes photosynthesis products to root and shoot system.
2 types: sieve tube cells, companion cells
Sieve tube cells
long, thin
Large pores through cell walls at either end
no nuclei, mitochondria or vacuoles
Arranged end-to-end into sieve tubes
cells share cytoplasm, each sieve tube forms channel for sugars and other products to flow
Companion cells
found alongside sieve tubes
Have nucleus, mitochondria and vacuoles
control activities of sieve tube cells
stomata
Tiny openings in surface of a plant leaf through which gases can enter or exit.
found on underside of leaf
From intecellular spaces, gases diffuse into cells that require them
central pore opening surrounded by 2 guard cells
Guard cell
pair of cells that open and close a stomata to control entry and exit of gases.
Change of water inside a pair of guard cells causes to change shape, open or close stomata
turgid
When guard cells swell with water
rigid inner wall and non-rigid outer wall, bend and draw away cells from each other, opening stomata.
Flaccid
shrink from lack of water
Closes stomata
mesophyll cells
Have chloroplasts
site for photosynthesis
Type of cell found in middle of leaves, packed with chloroplasts and essential for photosynthesis
pallisade cells
Elongated cell packed with chloroplasts
