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  • Veral wat watertekorte betref, is daar ’n wye reeks aanpassings en oorlewingstrategieë.
  • Xerofiete blare is gemodifiseer tot dorings in gevalle soos die kaktusplantgroepe. Ander stoor weer deur proteïenbindings baie water in hul vlesige blare, soos die aalwyn waaroor jy ’n projek moes doen.
  • Meestal is xerofiete se blare dik en vlesig en onaangenaam of bitter vir diere sodat dit nie deur hulle opgevreet word en so die plant van sy waardevolle vog ontneem nie.
  • Plante wat vir oorlewing in droë toestande aangepas is, se blare is dikwels sittend (geen blaarsteel) en op so ’n manier gerangskik dat water wat op die blaar versamel (bv. dou) teen die stam afloop sodat die wortels dit kan opneem.
  • Ander se blare rol op as dit droog is, sodat verdamping beperk word. Kyk bv. na mielieblare as dit vir ’n lang tyd nie gereën het nie.

Ontwerp jou eie xerofiet

  • Maak ’n skets om die aanpassings te toon indien jy die ontwerp sou doen.

Assessering van ONTWERP

Kon jy ’n sinvolle ONTWERP met logiese aanpassings TEKEN? [LU 1.3]

Diere:

By diere, anders as by plante, vind ons beide struktuurmodifikasies, asook gedrags­aanpassings om watertekorte die hoof te kan bied. Die meeste aan­passings is daarop gerig om waterverlies te beperk sodat die dier minder water hoef in te neem. In sommige gevalle het die dier ’n meganisme ontwikkel om water te kan stoor.

Voorbeelde van struktuuraanpassings

  • Huidbedekking
  • Insekte en spinnekoppe het ’n plastiek- of leeragtige huidbedekking (uitwendige skelet) wat geen water deurlaat nie. Dit beperk hulle behoefte aan water in so ’n mate dat die vog wat hulle saam met hul voedsel inneem, voldoende is.
  • Die vel van reptiele is ook aangepas om waterverlies tot die minimum te beperk. By ander diere waar die vel weens ander redes vogtig moet wees, is daar mega­nismes om onnodige waterverlies te voorkom. By paddas kan daar byvoorbeeld slym afgeskei word.
  • By voëls is daar ’n oliekliertjie op die punt van die stert wat olie afskei wat oor die hele liggaam versprei en die vere redelik waterdig maak (jy het miskien al gesien dat jou ma die kliertjie by ’n hoender uitsny voordat sy dit in die oond sit).
  • By soogdiere kan die vel aangepas wees om waterverlies tot die minimum te be­perk. Honde sweet byvoorbeeld deur hulle tong en baie min deur hulle vel. Dit is hoekom hulle hyg as hulle warm kry.
  • Inwendige aanpassings
  • Diere se spysverteringstelsels en uitskeidingstelsels is ook aangepas om water­verlies te kan reguleer. In die dikderm word byvoorbeeld baie van die water wat nog in die voedselreste teenwoordig is deur die liggaam opgeneem voordat ont­lasting plaasvind. Die niere, op hulle beurt, bepaal hoeveel water na die blaas deur­gelaat word om uitgeskei te word.
  • Die kameel is spesiaal aangepas om vir lang tye te kan oorleef sonder om water te moet inneem, deurdat water in die vorm van ’n chemiese verbinding in die boggel gestoor word en vrygestel kan word wanneer nodig.

Voorbeelde van gedragspatrone

  • Verdamping van water is ’n algemene afkoelingsmeganisme by diere. Dit is vir die mens byvoorbeeld belangrik om te kan sweet sodat die verdamping van die sweet kan voorkom dat die liggaamstemperatuur te veel styg, hetsy omdat dit baie warm is of weens strawwe oefening. Diere openbaar dus dikwels gedragspatrone waar­deur die liggaam koel gehou word sodat afkoeling deur ander meganismes, soos bv. sweet, nie nodig is nie. Hulle kan byvoorbeeld skaduwee opsoek, tonnels gra­we, onder die sand lê, bedags onaktief wees of selfs migreer of in ’n somerslaap gaan.

Questions & Answers

where we get a research paper on Nano chemistry....?
Maira Reply
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
Google
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
revolt
da
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
Nasa has use it in the 60's, copper as water purification in the moon travel.
Alexandre
nanocopper obvius
Alexandre
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
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Source:  OpenStax, Natuurwetenskappe graad 8. OpenStax CNX. Sep 12, 2009 Download for free at http://cnx.org/content/col11049/1.1
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