Energy in Ecosystems A. 1. 2.

Name
Date
Class
Chapter 20
LESSON 3
Lesson Outline
Energy in Ecosystems
A. How does energy move in ecosystems?
1. Matter
through an ecosystem.
2. Energy
through an ecosystem.
3. Energy can change form as it moves through an ecosystem, but the total
amount of energy
the
. This rule is called
.
4. Organisms that make their own food are
a. The process of
.
uses light energy to make food and
oxygen from carbon dioxide and water.
b.
makes food using chemical energy instead of light
energy.
5.
obtain energy by eating other organisms.
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
a. A(n)
eats only plants.
b.
are animals that eat other animals.
c.
eat producers and consumers.
d. Consumers called
eat dead organisms.
e. Another name for bacteria and mushrooms is
f. Decomposers help cycle
.
through ecosystems.
B. Modeling Energy in Ecosystems
1. As energy changes from one organism to another in an ecosystem, some stored
chemical energy changes to
energy.
2. A(n)
is a model that shows how energy flows in an
ecosystem through feeding relationships.
C. Food Webs
1. When you overlap the food chains in an ecosystem, the result is
a(n)
2. In a food chain and a food web,
.
show the movement
of energy.
Matter and Energy in the Environment
43
Name
Date
Class
Lesson Outline continued
D. Energy Pyramids
1. A(n)
shows the amount of energy available in each step
of a food chain.
2. The steps of this energy model are called
.
a. The bottom layer of an energy pyramid contains
.
b. The middle layer of an energy pyramid contains consumers that
eat
.
c. The top layer of an energy pyramid contains consumers that
eat
.
3. Only about
percent of the energy in one step of an
energy pyramid transfers to the next higher step.
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
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Matter and Energy in the Environment