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Natuurwetenskappe

Die aarde en daarbuite

Fossiele

Opvoeders afdeling

Memorandum

Opdrag 9:

  • Hulle het vroeër in woude gelewe.
  • Het nie nodig gehad om vinnig te kon hardloop nie.
  • Korter bene was voldoende om in woude te kon oorleef.
  • Word vandag in oop vlaktes aangetref.
  • Moet vinnig kan hardloop vir vyand.
  • Langer, meer gespierde bene help om te oorleef.
  • Word gebruik om op te ry en karre te trek.Het groter en sterker geword sodat dit ‘n effektiewe vervoermiddel kon word.

Leerder afdeling

Inhoud

Aktiwiteit: om die verandering van organismes met die verloop van tyd te kan bespreek [lu 2.3]

Plante en diere verander gedurig om aan te pas en beter in hul omgewings te kan oorleef. Die omgewing verander egter ook. Dit is waarom die dierelewe oor die eeue heen verander het.

  • Gedurende die tydperk van die dinosourusse was die wêreld meestal warm en droog. Geleidelik het die klimaat begin verander, nuwe diere en plante het begin ontwikkel en ander het uitgesterf. Soos die klimaat warmer en natter geword het, het groot woude van reuse varings en allerlei keëldraende bome ontstaan. In hierdie veranderende wêreld moes die dinosourusse ook verander om te kon oorlewe. Omtrent 100 miljoen jaar gelede het daar blomplante en bloeiselbome verskyn en stadigaan het daar woude van lourier- en eikebome begin groei. Voëls, insekte en ander diere het begin ontwikkel om die nektar en stuifmeel van die blomme te vreet.
  • Die dinosourusse het almal verdwyn, maar hulle het afstammelinge nagelaat. Indien fossiele bestudeer word, blyk dit dat krokodille en voëls die naaste lewende familie van die dinosourusse is. Die dinosourusse was wel reptiele, maar die reptiele het reeds 300 miljoen jaar gelede ontwikkel. Reeds voor die dinosourusse verskyn het, het die reptiele al in talle verskillende groepe vertak.

Verandering van organismes:

  • Sommige diere, soos bv. die kakkerlak, het oor miljoene jare byna niks verander nie. Om te oorleef moes ander diere egter aanpas en het hulle met verloop van tyd drasties verander. Perde was eens so groot soos ‘n terriër en het in woude gebly. Vandag is hulle vinnige langbeendiere wat op oop vlaktes bly. Dit staan bekend as natuurlike seleksie.

Prehistoriese Lewe, Van den Heever et al., p. 19

OPDRAG 9

  • Bespreek die rede vir bogenoemde aanpassings by perde eers in julle groepe. Skryf dan ‘n paragraaf waarin jy ten minste vyf moontlike redes verskaf vir hierdie verandering.

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LeerkragassesseringKRITERIA 1. 2. 3. 4.
1. Opdrag korrek voltooi.
2. Sinvolle inhoud
3. Kreatiewe denke openbaar.

Assessering

Leeruitkomste 2: Die leerder ken, interpreteer en pas wetenskaplike, tegnologiese en omgewingskennis toe.

Assesseringstandaard 2.3: Dis duidelik wanneer die leerder inligting interpreteer.

Questions & Answers

how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
Maciej
Do somebody tell me a best nano engineering book for beginners?
s. Reply
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
Virgil
is Bucky paper clear?
CYNTHIA
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
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Cied
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
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Cied
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
many many of nanotubes
Porter
what is the k.e before it land
Yasmin
what is the function of carbon nanotubes?
Cesar
I'm interested in nanotube
Uday
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
AMJAD
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
AMJAD
what is system testing
AMJAD
what is the application of nanotechnology?
Stotaw
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
Azam
anybody can imagine what will be happen after 100 years from now in nano tech world
Prasenjit
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
Azam
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
Prasenjit
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Damian
silver nanoparticles could handle the job?
Damian
not now but maybe in future only AgNP maybe any other nanomaterials
Azam
Hello
Uday
I'm interested in Nanotube
Uday
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
Prasenjit
can nanotechnology change the direction of the face of the world
Prasenjit Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
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Source:  OpenStax, Natuurwetenskappe graad 6. OpenStax CNX. Sep 17, 2009 Download for free at http://cnx.org/content/col11080/1.1
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