9,5 Adaptation Flashcards
Basic adaptations of leaf first
- stomata on UNDERSIDE of leaf to prevent evaporation as much
- waxy cuticle to prevent water loss
- roots growing far as pssobel
Xerophyte vs hydrophyte
An exerophyte is a plant that lived under dry hot conditions where amount fo water is very low,and hydrophyte is when amount of water very abundant, bith need to sdslt
What xerophthalmia we need to know and hydrophyte
Xerophyte & marram grass and cacti
Hydrophyte = water lilly
General adaptations of xeropjyted
- thicker waxy cuticle than normal
SUNKEN STOMATA - stomata re sunken in pits, this reduces air mofment snd creates a microclimate of still air, which decreases conc grsdient and thus rate of transpiration - that is humid
3) reduced stomata
Leaves
4) leaves as thin needles - reduces sa: v ratio , which reduces transpiration as less area to evaporate fro,
5) hair leaves - also create microlimateof still humid air thst rescue conc and trnapristiojn. - marram grass has microhiaesin sunken stomata pit too
6) curled leaves = again , creates microclimate of humid air again, marram grass
7) succulents
- this is where water is stored in SPECILAISED parenchyma tissue, and done in plentiful supply and sued in drought, here this found in aloe Vera etc and cacti
8) leaf loss
- leaves are just shredded when water not available, reduces water loss but ate last can stay alive
Roots
- deep roots, but also shallow roots to collect rainwater before evaporate
- marram grass root contains long vertical roots that oentrate sand, and then have a mat of horizontal rhizomes which are modified stems and forms extensive network to collect rain
- can avoid the problem
- here might get sucked to allow seeds a chance when water falls again , others survive as storage organs in bulbs etc snd grow form there again
- some plants look completely desd but can become alive again in the presence of water too
Okay so steufture of xeroyphyets
Waxy cuticle
- sunken stomata , reduced stomata
- Hairs, and microhairs on stomata
- specialised parenchyma water storage tissue when plenty store and use in drought
LEAVES
- as needles to reduce as:v , curdled so microclimate, or just leaf loss when water low
Roots?
Roots are deep and shallow to collect rain best case
Vertical roots with hroinxitsl met of rhizomes,mehichnsre dpeiclsised stems in marram grass, create a network that can get rain even better snd adapt to their current environment
Avoid problem
Die, or appear dead snd revive when water shout
- can also shed leaves and make the stem green sgsin
Survive as storage organs
Adaptations specifically for marram grass (think roots leaves etc)
- sunken stomata in pits for microclimate, with microhairs on these pits too to emphasise effect
- curled leaves for microclimate too
Roots= long vertical roots that have. Horizontal mat of rhizomes that form network to collect water better and adapt to changinf environment
This is best fo both worlds
Waxy cuticle
Sunken stomata with hair in this
Leaves are curled
Roots horizontal sndveticall
Sunken stomata with microhairs in them
Leaves are curled
Roots
Cuticle
Sunken stomata and hair in them
Cuticle waxy
Roots
Curled
Cacti
- thick waxy cuticle on epidermis
- SPINES INSTEAD OF LEAVES = less leaf as so less water lost
- sunken stomata and stomata closed when hot
- specialised parenchyma succulent store water
- roots are deep and shallow
- spines instead of leaves
- sunken stomata
- closes at hottest point
- specilaised larenchyma succulent
Roots are deep but also shallow
- thick waxy cuticle
Okay adaptations for both marram grass and cacti
Marram first
- thick waxy cuticle
- stomata is sunken fir microclimate and there are microhairs too for better effects
- leaves are curled
- roots long snd verritcal but also horizontal mat of rhixomes specialised stems so both good and adapt
Cacti - thick waxy cuticle X sunken stomata , that close when light intensity the highest - spines instead of leaves reduce as - specilissed larenchyma - roots long and shallow
Situation of hydrophytes
Too much water , so need to ensure to float so that they can get enough light for photosynthesis and so air spaces not to be full of worn and not water to survive, or else it will drown
Need oxygen because lack of that
Basic adaptations of hydrophytes
- very thin cuticle, don’t need to conserve water so this is kinda pointless
- stomata is ALWAYS OPEN, and also ON UPPER SIDE (rather than lower). No need to be scared of water loss, not possible, so they can always be open and guard cells pretty much inactive , also has to be upper side so gas exchange can happen
- reduced structure to the okant, as not needed as water supports most of plant by floating
- leaves are WIDE and flat across the water so as ,icy light can be absorbed as possible
- small roots too, water can diffuse DIRECKTY into leaves so transport system extensive not needed, it’s a waste
- air sacs to float
And AERNCYHMA
# this is specilsiedparenchyma tissue which forms in leaves roots and stem .
- it has many large air soades which is for,Ed by apoptosis of the normslmlerwncnyma tiddue , snd this gives two uses ,
1) makes the leaves and stems more Bryant’s no float
- but also provides low resistance pathway for ,ofement of oxygen and others below the water , and this helps plant cope with conditions where oxygen is scarce, such as mud, and leg those particles of plant still get oxygen they need by transporting oxygen
Again
Okay so
- stomata always open and on top
- reduced structure to plant as a lot held by water, so less roots too
- leaves wide to get more light intensity
# and roots small because atercan go on inauwss
- no waxy cuticle doesn’t need
Air sacs
- specialised parenchyma tissue arendhyma which is parenchyma tissue with air spaces, csused by apoptosis of pranncyms, gives buoyancy but also low resistsnce internal pathway to roots and stems to transfer oxygen, making it easier, and better for condtionswith lack of oxygen like mud, can still survuve
- stomat open and on top
- reduced structure = not needed as leaves held, roots small as transport system not needed there as can just diffuse in
- have air sacs
NO CUTICLE - leaves wide
- arenchyma
Adaptation specially for water lillie d
- probably no cuticle
- stomata always open and on top
- wide leaves
- reduce structure and small roots
- and basically arenchyma so specialised paremchyma buoyancy and low resistance pathways to trnadfer oxygen to tiger structure dmskimg it easier when anoxic like mud
If plant completely submerged?
It grows roots outwards somair can be taken in fromhere too
