Food chains
A food chain shows the different organisms that live in a
habitat, and what eats what.
Producers and consumers
A food chain always starts with a producer, which is an organism
that makes food. This is usually a green plant, because plants can make their
own food by photosynthesis.
A food chain ends with a consumer, which is an animal that eats
a plant or another animal. Here is an example of a simple food chain:
grass → cow → human
Take care - the arrow points to the organism that is doing the
eating. If you get the arrows the wrong way round, instead of showing that
humans eat cows, you are showing that cows eat humans, and that grass eats
cows.
Other words in a food chain
There are several words used to describe the organisms in a food
chain. Study this food chain:
The plant is the producer and the animals are consumers.
Notice that the first consumer in the chain is also called the
primary consumer, the next one is the secondary consumer and the one after that
is the tertiary consumer.
A consumer that eats plants is called a herbivore, and a consumer that eats
other animals is called a carnivore. An omnivore is an animal that eats both
plants and animals.
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Grass
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→
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Grasshopper
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→
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Frog
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→
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Hawk
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 |
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 |
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 |
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Producer
|
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Consumer
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Consumer
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Consumer
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Primary consumer
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Secondary consumer
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Tertiary consumer
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Herbivore
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Carnivore
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Carnivore
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Predators and prey
A predator is an animal that eats other animals, and the prey is
the animal that gets eaten by the predator. In the food chain above:
·
the frog is a predator and the grasshopper is its prey.
·
the hawk is a predator and the frog is its prey.
Food chains - Test
1.What are the products of
photosynthesis?
2.What colour is chlorophyll?
3.Where does photosynthesis
take place?
4.A green plant is usually a:
5.What does a food chain
always start with?
6.Which is the secondary
consumer in this food chain:
grass -> grasshopper ->
frog -> hawk
7.What does an omnivore eat?
