12 – 1 What are producers and consumers?
Producers
Almost all energy that is used by living things comes from the Sun. Organisms that use the
Sun’s energy to make their own food are called producers. On land, the main producers
are plants. The main producers in lakes and oceans are algae and phytoplankton.
Consumers
Most types of organisms cannot make their own food. Instead, they get energy by eating
other organisms. An organism that eats other organisms is a consumer. Some consumers
eat only plants. They are called herbivores. Rabbits are herbivores. They eat grass and
other plants. Some consumers only eat animals. They are called carnivores. Lions are
carnivores because they eat other animals. Other consumers are omnivores. Omnivores
eat both plants and animals. Humans are omnivores because we eat plants and animals.
Levels of Consumers
A primary consumer is an organism that eats producers. Most
herbivores are primary consumers. Caterpillars eat leaves and
other plants. They are primary consumers. Organisms that eat
primary consumers are secondary consumers. Tree frogs eat
small plant-eating animals, such as caterpillars and butterflies.
Tree frogs are secondary consumers. Consumers that eat
secondary consumers are called tertiary consumers. Toucans are
birds that eat small meat eating animals, such as tree frogs and
snakes. Toucans are tertiary consumers.
Some animals, such as toucans are both secondary and tertiary
consumers. Most humans are primary, secondary, and tertiary
consumers.
Scavengers and Decomposers
Some animals feed on dead animals. These animals are scavengers. Scavengers eat
animals that have died or been killed by other animals. Vultures, hyenas, and certain ants,
beetles, and worms are scavengers. Scavengers can be both secondary and tertiary
consumers. Organisms that break down the waste or remains of organisms are
decomposers. Decomposers return materials from dead organisms to the soil, air, and
water. Most bacteria and fungi are decomposers.
12-1 What are producers and consumers?
Lesson Review
Match each term in Column B with its description in Column A. Write the letter of
the correct term in the space provided.
Column A
Column B
_________ 1. organism that makes its own food
a. producer
_________ 2. animal that eats dead organisms
b. secondary consumer
_________ 3. animal that eats plant-eating animals
c. decomposer
_________ 4. organism that breaks down the wastes or remains
of other organisms
d. tertiary consumer
e. scavenger
_________ 5. animal that eats meat-eating animals
f.
_________ 6. main producers in lakes and oceans
algae and
phytoplankton
_________ 7. consumer that eats only plants
g. omnivore
_________ 8. consumer that eats only animals
h. herbivore
_________ 9. consumer that eats both plants and animals
i.
carnivore
Skill Challenge
Skills: classifying, applying concepts
Classify each organism listed in the table as a producer, consumer, scavenger, or
decomposer. Place a check mark in the correct column.
CLASSIFYING ORGANISMS
Organism
1. Seaweed
2. Duck
3. Hawk
4. Hyena
5. Bacteria
6. Vulture
7. Rabbit
8. Grass
9. Apple tree
10. Fungus
Producer
Consumer
Scavenger
Decomposer
CHECKING CONCEPTS
1. Producers use energy from the
to make their own food.
2. Some producers in lakes are
.
3. Organisms that eat the remains of dead animals are
4. Organisms that eat only producers are
5. Secondary consumers are eaten by
.
consumers.
.