Today we will:
KNOW:
» The Sun is the main source of energy on Earth, green
plants are able to harness this energy via
photosynthesis and are categorised as producers.
» Plants are a source of energy and nutrients for the
other organisms.
BE ABLE TO:
» Recognise that plants use photosynthesis to produce
food.
» Understand that animals cannot create their own
food therefore rely upon plants.
Think about the following questions and put your
ideas on paper.
» How important do you think the environment is
for life? Explain.
» Are there some parts of YOUR environment that
you couldn’t live without? List them and explain.
» If you were forced to live in the Australian desert
for a year, what would you need to keep in mind
to survive?
» We can classify living things in many different
ways. Today, we will classify them based on
what they eat.
Can you list some other ways living things are
classified?
» The Sun is the main source of energy on Earth.
» Plants are the only living things which can absorb
the Sun’s energy and transfer it into chemical
energy to live.
» This is a process called PHOTOSYNTHESIS.
There is something in
leaves called
CHLOROPHYLL that
helps them absorb light
energy from the sun and
helps make leaves look
green.
Next week in prac, we
will be seperating the
different colours found
in some leaves.
» Animals can’t make their own energy. They need
to take it from other sources. Therefore they are
called consumers.
» Plants are called producers.
They are herbivores - eat primary producers (plants).
Second order Consumers (carnivores) - eat primary
consumers (herbivores).
Fourth Order
Consumer
Third Order
Consumer
Second Order
Consumer
First Order
Consumer
Producer
4th order consumer
3rd order consumer
2nd order consumer
1st order consumer
Producer
The Pond
Fungi – Example: Mushrooms
Bacteria
Some insects like the dung
beetle
Whenever something that was alive dies, the decomposers get
it. Decomposers break down nutrients in the dead "stuff" and
return it to the soil. The producers can then use the nutrients
and elements once it's in the soil. The decomposers complete
the system, returning essential molecules to the producers.
Do you like to play games? If you do, you will need energy. Every
time you run or jump, you are using up energy in your body.
How do you get the energy to play? You get energy from the
food you eat. Similarly, all living things get energy from their
food so that they can move and grow. As food passes through
the body, some of it is digested. This process of digestion
releases energy.
A food chain shows how each living thing gets its
food. Some animals eat plants and some animals eat
other animals.
Each link in this chain is food for the next link. A food
chain always starts with plant life and ends with an
animal.
» The feeding
relationships between
producer and
consumers can be
written down in the
steps called a food
chain.
» Each arrow indicates
“is eaten by”. It also
shows the flow of
energy.
» There cannot be too many links in a single food
chain because the animals at the end of the chain
would not get enough food (and hence energy) to
stay alive.
» Most animals are part of more than one food
chain and eat more than one kind of food in order
to meet their food and energy requirements.
These interconnected food chains form a food
web.
If you’re a little confused, look at it this way…
» FOOD CHAIN…
It actually looks like a chain, there is one link after
another.
» FOOD WEB…
It looks a little like a spider’s web, full of aroows going
in all sorts of directions.
»Find at
least 3
food chains
in the
following
food web.
W/S: Food Webs 1 & 2
Match the word to the meaning.
Word
Meaning
Herbivore
An animal that eats only plants
Producers
Organisms that make their own food
Omnivores
Animals that eat plants and animals
Consumers
Organisms that eat other organisms or their products
Carnivores
Animals that eat only meat (other animals)
Decomposers
Bacteria & Fungi which breakdown plant and animal remains
Food Chain
A feeding relationship between producers & consumers
Food Web
When many food chains are interlocked together
Why Do
Herbivores Need
to Eat MORE than
Carnivores?
» Animals move around and loose their energy as
heat (perspiration) and as waste (excretion of
urine and faeces – poo!)
» Plants do not loose a lot of energy because they
do not move or digest their food.
What Human
Impacts on the
Environment Can
YOU Think Of?
»The three largest impacts:
˃Deforestation
˃Agriculture
˃Introduced Species
DEFORESTATION
Deforestation is the removal of a
forest or stand of trees where the land
is thereafter converted to non-forest
use.
AGRICULTURE
Agriculture is the use of land for crops
and farming. Damage is done by: land
clearing, irrigation, soil use, adding
fertilisers/chemicals etc….
INTRODUCED SPECIES
Introduced species are foreign species
that have arrived accidentally or have
been introduced to a new area.
Read the following paragraph about who eats whom in the Antarctic and draw a
food chain that shows the feeding relationships in this habitat.
Don’t forget that your food chain must start with a producer!