Energy Transfer Through an
Ecosystem
Table of Contents
Date
Title
Page
2/26/13
Energy Transfer in an
Ecosystem
5
Goal: Students will determine how energy
travels through ecosystems by identifying the
relationships between producers, consumers,
and decomposers.
Recall: How is an ecosystem
different from a community?
What types of communities do you see in
this picture? What type of ecosystem is it?
Remember…
• An ecosystem is the total of living
parts (plants and animals) and
nonliving parts (sunlight, air, water,
soil) that support life in a unit of
nature. We can refer to the Earth as
one ecosystem or divide it into
smaller units with similar
characteristics.
How is the energy role determined?
• An organism’s energy
role is determined by
how it obtains food and
how it interacts with
other organisms.
– Do you play an
instrument?
• Each instrument has a role in a
piece of music. Similar to the
instruments in a band, each
organism has a role in the
movement of energy through its
ecosystem
The living parts of an ecosystem can be
divided into three categories:
Producers: Organisms that can make their own
food. Ex. Plants have chlorophyll and can
produce their own energy in the form of
carbohydrates (simple sugars) through
photosynthesis.
Consumers
Animals must consume
something else, either
plants or other animals,
to get their energy.
There are different levels of
consumers:
top carnivores-eats other
carnivores (ex. Wolf)
carnivores -eats other
animals (ex. Snakes)
omnivores-eats plants and
animals (ex. Humans)
herbivores-eats only
producers (plants) (ex.
Rabbits)
Decomposers
Decomposers: break
down biotic wastes
and dead organisms
and return the raw
materials to the
ecosystem.
“Nature’s Recyclers”
In any community, energy flows from
producers to consumers.
• Energy moves through
the ecosystem in the
form of food
• When organisms die,
decomposers obtain
energy when they break
down the bodies of
dead organisms
Food Chain
• A food chain is a simple
way of showing how
energy (food) passes
from one organism to
another
• Arrows between
organisms indicate the
direction that the
energy is moving
Food Chains (con’t)
• Usually have 3 or 4 links
• At each transfer of
energy, a portion of the
energy is lost as heat
due to the activities or
organisms as they
search for food and
mates
Food Webs
• A food web is a series of
overlapping food chains
• Organisms play more
than one role in an
ecosystem.
• Remember the rule
about the arrows!
A Food Web Example video
Create a Food Web
•
•
•
•
•
•
Label:
Producers
Primary Consumers
Secondary Consumers
Tertiary Consumers
Decomposers
• Include arrows moving
in the appropriate
direction following the
direction that the
energy is being used
• Primary (first-level) consumers eat producers
• Secondary (second level) consumers eat
primary consumers
• Tertiary (third level) consumers eat secondary
consumers
• THE FIRST ORGANISM IN THE FOOD
CHAIN/WEB IS ALWAYS A PRODUCER
After you create your food web…
• Using your food web, answer the following
questions:
• (a) Which organisms are producers?
• (b) Which organisms are first order
consumers?
• (c) Which organisms are second order
consumers?
• (d) Which organisms are third order
consumers?