The document discusses the environment, ecosystems, biodegradable and non-biodegradable waste, food chains, producers and consumers in ecosystems, chlorofluorocarbons (CFCs) and their impact on the ozone layer, and effects of ozone layer depletion. It provides definitions and examples for each topic.

2. • The physical and biological world
where we live is called our
environment.
• The environment includes our physical
surroundings like air , water bodies ,
soil (land)and all the organisms such
as plants , animals, human beings and
micro-organism like bacteria and
fungi (called decomposers).

3. • Those wastes materials which can be broken down to
harmless or non-poisonous substances in nature in
the due course of time by the action of micro-organism
like certain bacteria, are called
biodegradable wastes.
• A biodegradable waste decays(decomposes) naturally
and becomes harmless after some times.
• Examples :- cattle dung , compost , sewage , paper ,
cloth , wood etc.

4. • The materials which cannot be broken down into
non-poisonous or harmless substances in nature are
called non-biodegradable wastes.
• Examples :-D.D.T. (Dichloro Diphenyl Trichloroethane)
, plastics , polythene bags , synthetic fibres ,
radioactive wastes etc.

5. • It is the structural and functional unit of
biosphere, comprising of all the biotic and
abiotic components of the environment.
• Thus, an ecosystem is a self sustaining
system where energy and matter are
exchanged between living and non-living
components.

6. • Natural ecosystem :- The natural ecosystem
is terrestrial as well as aquatic. For example,
forests , grasslands , deserts , ponds , lakes
etc.

7. • Artificial ecosystem :- are made by human
beings.
• For example:- crop field , gardens , parks ,
aquarium, etc.

8. • Anything which we eat to live is called food.
• The food can be transferred from one
organism to the other through food chain.
Energy is transferred by the process of one
organism consuming the other.
• Example of a simple food chain
• Plants  Worms  Birds  Cat

10. .
• Producers are the organisms which can prepare
their own food from simple inorganic substances
like carbon dioxide and water by using sunlight
energy in the presence of chlorophyll.
• The examples of producers are Green plants and
certain blue-green algae.
• This are called autotrophs.

11. • Primary consumers (herbivores) occupy the second level in the
food chain. This organisms feed upon plants.
• Some examples of herbivores are cow, goat, sheep , camel,
elephant, etc.
• Carnivores ( that feed upon herbivores ) constitute the third
trophic level. They are the secondary consumers.
• Some examples of carnivores are fox, jackal, bear, frog, etc.

12. • Large carnivores or top carnivores (which
feed upon small carnivores), constitute the
fourth tropic level. They are the tertiary
consumers.
• Some examples of tertiary consumers are
lion, tiger, hawk, etc.

13. • The 10 per cent law which was given by
Raymond lindeman in the year 1942, is one
of the most useful generalisation about the
magnitude of loss of energy in food chains.

14. • According to 10 per cent law, only 10 per
cent of the energy entering a particular trophic
level of organisms is available for transfer to
the next higher trophic level.
• The energy available at each successive trophic
level is 10 per cent of the previous level.

17. • This compound’s highly stability to temperatures
makes them suitable for a variety of uses such as in
aerosols and refrigerators coolants. They are often
known as freons.
• CFCs are stable. They do not degrade easily and rise to
the stratosphere, where they are broken down by UV
radiation resulting attack on the ozone molecules
damaging the ozone layer.

19. • There are several reasons for the depletion of ozone layer :-
• The foremost reason is the use of CFCs. The other factor
responsible for the destruction is the pollutant nitrogen monoxide
(NO).
• When this harmful chemicals like CFCs are released into the air it
accumulates in the stratosphere and reacts with the ozone layer
by forming a hole.
• Thus, the ozone layer becomes thinner and gets depleted allowing
more UV rays to pass through the earth.

20. Due to the depletion of ozone layer, ultraviolet rays
causes ill effect which are globally bad and harmful.
• For example :- skin cancer , cataract and certain
other problems to our immune system.
Skin cancer
cataract