FOOD CHAINS
A.Sharma
´ A food chain is a linear diagram that shows the feeding relationship between
organisms and the flow of energy from one organism to the next.
´ An arrow is used between each organism to show the direction of flow of energy.
Producer: A producer is an organism that produces its own food through
photosynthesis. Producers are at the start of the food chain.
o Producers for example green plants, grasses, seaweed or algae, make their own
food using sunlight through the process of photosynthesis and are therefore at
the start of a food chain.
Consumers- Are organisms that eat other organisms.
o They can be – Herbivores- Animals that only feed on plants.
Carnivores-Animals that only feed on animals.
Omnivores- Animals that feed on both plants and animals.
Primary Consumer: A primary consumer is an organism that feeds directly on producers.
They are herbivores that consume plants to obtain energy. Primary consumers occupy
the second trophic level in a food chain.
Secondary Consumer: A secondary consumer is an organism that feeds on primary
consumers. They are carnivores or omnivores that eat herbivores or other primary
consumers for energy. Secondary consumers occupy the third trophic level in a food
chain.
Tertiary Consumer: A tertiary consumer is an organism that feeds on secondary
consumers. They are typically apex/top predators in an ecosystem, feeding on other
carnivores or omnivores. Tertiary consumers occupy the fourth trophic level in a food
chain.
Quaternary Consumer- Quaternary consumers are often top predators within the
environment, and they eat the tertiary consumers.
TROPHIC LEVELS-
, o The feeding positions in a food chain.
o Each trophic level represents a step in the transfer of energy
The image bellow summarizes the types of consumers and trophic levels.
TYPES
OF FOOD CHAINS-
Aquatic food chains- These are found in aquatic ecosystems such as: ponds, rivers, oceans.
Example-
Terrestrial food chains- These are found on land ecosystems such as: grasslands, forests.
Example-
A.Sharma
´ A food chain is a linear diagram that shows the feeding relationship between
organisms and the flow of energy from one organism to the next.
´ An arrow is used between each organism to show the direction of flow of energy.
Producer: A producer is an organism that produces its own food through
photosynthesis. Producers are at the start of the food chain.
o Producers for example green plants, grasses, seaweed or algae, make their own
food using sunlight through the process of photosynthesis and are therefore at
the start of a food chain.
Consumers- Are organisms that eat other organisms.
o They can be – Herbivores- Animals that only feed on plants.
Carnivores-Animals that only feed on animals.
Omnivores- Animals that feed on both plants and animals.
Primary Consumer: A primary consumer is an organism that feeds directly on producers.
They are herbivores that consume plants to obtain energy. Primary consumers occupy
the second trophic level in a food chain.
Secondary Consumer: A secondary consumer is an organism that feeds on primary
consumers. They are carnivores or omnivores that eat herbivores or other primary
consumers for energy. Secondary consumers occupy the third trophic level in a food
chain.
Tertiary Consumer: A tertiary consumer is an organism that feeds on secondary
consumers. They are typically apex/top predators in an ecosystem, feeding on other
carnivores or omnivores. Tertiary consumers occupy the fourth trophic level in a food
chain.
Quaternary Consumer- Quaternary consumers are often top predators within the
environment, and they eat the tertiary consumers.
TROPHIC LEVELS-
, o The feeding positions in a food chain.
o Each trophic level represents a step in the transfer of energy
The image bellow summarizes the types of consumers and trophic levels.
TYPES
OF FOOD CHAINS-
Aquatic food chains- These are found in aquatic ecosystems such as: ponds, rivers, oceans.
Example-
Terrestrial food chains- These are found on land ecosystems such as: grasslands, forests.
Example-
