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To brush up your knowledge of eco-systems

Natural sciences

Life and way of living

Educator section


1. organisms



2. producers/manufacturers (food producers)





3. Location, climate, soil, water, atmospheric gases (more specific factors may also be listed, e.g. slope and south- /east-/ west-/ north-facing instead of location, or temperature, rain and wind instead of climate)


1. All materials are recycled in nature and that is why the resources are not depleted. Whatever is taken from the soil or the air is eventually returned to it.

2. Water: from the soil to plants and animals (and into the air), back to the soil (urine and faeces) or air (perspiration, evaporation).

Carbon dioxide: from the air to the plant, fixed in food, to the animal, released into the air.

Components in the soil to the plant, forming nutrients, to animal that eats the plant, returning to the soil with urine or faeces, or when the plant or animal dies

3. To prevent depletion of natural resources/ substances being used up

Leaner section


Activity 1: to brush up your knowledge of eco-systems [lo 2.1, 2.3]

The ecosystem

Test your knowledge

You were introduced to the concept of the ecosystem in Grade 6. Let us see how much you can remember:

Complete: An ecosystem is all the living ___________________ that live in a

specific _________________ as well as all the __________________ factors

that determine the nature of the environment.

In an ecosystem, the plants are the ____________________ while the animals

are the _______________________ Animals can be divided into three groups

on the basis of their manner of feeding, namely _______________________,

___________________________ and _______________________________

The non-living factors which determine conditions in the ecosystems are

_______________________________, _____________________________,

_______________________________ and ___________________________ .

Cycles and balance within an ecosystem

An ecosystem can be represented diagrammatically as follows:

Try to answer the following questions that deal with the diagram:

1. Why is the ecosystem represented as a cycle?








2. Name three substances/compounds that are circulated in an ecosystem according to the diagram, and give a brief description of each cycle:








3. Why is it important for the substances to be circulated?









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

Assessment Standard 2.1: We know this when the learner recalls meaningful information (at least definitions and complex facts);

Assessment Standard 2 .3 We know this when the learner interprets information.

Questions & Answers

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 ?
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
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.
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.
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
many many of nanotubes
what is the k.e before it land
what is the function of carbon nanotubes?
I'm interested in nanotube
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
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
what is system testing
what is the application of nanotechnology?
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
anybody can imagine what will be happen after 100 years from now in nano tech world
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
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
silver nanoparticles could handle the job?
not now but maybe in future only AgNP maybe any other nanomaterials
I'm interested in Nanotube
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
Ali Reply
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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