The biotic component is
that part of the total
environment created by
A biological community
together with the abiotic
by the flow of energy and
the cycling of inorganic
The sun which is the primary source of energy, gives
energy to the plants to produce food through
Plants use the light, carbon dioxide, water and the green
pigment chlorophyll in their leaves to produce sugars and
These plants that produce food through photosynthesis are
They are autotrophic organisms because they can
manufacture their own food.
Animals are consumers because they are, directly/indirectly
dependent on the food produced by the producers (plants), they
consume this food.
Consumers therefore have a heterotrophic feeding method –
they cannot make their own food and are dependent on the
producers for nutrition.
Decomposers are micro-organisms that break down complex
organic matter into simple inorganic matter.
They obtain their energy for the decaying animals and plants.
They are heterotrophic animals.
We refer to them as saprophytic organisms.
They include fungi and bacteria.
The interaction of the autotrophic and heterotrophic
components in which one organism
consumes another, is called a food chain.
In a food chain there is a continuous flow of energy from
the sun, through the plants to the various animals.
In a food chain there are always a producer and a
Try answer these questions to
test your knowledge:
What is a biotic component?
Give the definition of an ecosystem.
What components form part of an ecosystem?
Briefly describe each of these components.
What is the difference between a food chain and a
Draw an example of each.(It must be your own