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Natural sciences

Planet earth and the universe

The earth

Educator section


Leaner section


Activity: to represent the different layers in the earth’s atmosphere visually and to investigate weather patterns and seasons [lo 2.3, lo 3.1]


A layer of air called atmosphere envelops the earth. This layer usually contains two gases, namely oxygen (78%) and nitrogen (20%). The atmosphere consists of a number of layers, of which each has its own characteristics.


  • Troposphere

This is the layer closest to Earth. Here we find all the weather patterns and clouds, and this is also where aeroplanes and birds fly.

  • Ozone layer

The harmful ultra-violet rays of the sun are absorbed in this layer.

  • Stratosphere

It is here that modern jets fly. Oxygen supply is insufficient for man to breathe.

  • Mesosphere

Most small meteors burn out in this layer.

  • Thermosphere

Most of the sun’s heat is absorbed here; temperatures rise to 1 000 degrees Celsius.

  • Ecosphere

There is almost no air in this layer. Only the lightest of gases are found here, as well as some weather satellites.

The above-mentioned layers do not have fixed limits and we can therefore say that they intermingle. The density decreases the higher the layer is until almost no air is present. Compared to the cross-section of the earth, the atmosphere is not really a very thick layer.


Group work

  • Using the information given, make a diagrammatical representation of Earth, showing all its layers.
  • Use different colours to distinguish between the layers.
  • Labels must be in print.
  • The thickness of layers must be displayed.
Educator Assessment: Diagrammatical Rrepresentation 1. 2. 3. 4.
1. Aim: The message is carried over clearly
2. Detail: Detail is accurate and clear
3. Sketches and illustrations: Functional and purposeful
4. Creativity: Representation is creative and original
5. Presentation: neat and orderly
DOMINANT CODE: ........MARK: ......./ 20 ..............%Educator:..................................................






Learner: _____________________________________________________________


Learning Outcome 2: The learner will know and be able to interpret and apply scientific, technological and environmental knowledge.

Assessment Standard 2.3: We know this when the learner interprets information: interprets information by identifying key ideas in text, finding patterns in recorded data, and making inferences from information in various forms (e.g. pictures, diagrams, text).

Learning Outcome 3: The learner will be able to demonstrate an understanding of the interrelationships between science and technology, society and the environment.

Assessment Standard 3.1: We know this when the learner understands science as a human endeavour: compares differing interpretations of events.

Questions & Answers

what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
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
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
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
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
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.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
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.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Natural sciences grade 7. OpenStax CNX. Sep 16, 2009 Download for free at http://cnx.org/content/col11077/1.1
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