Energy Flow

ENERGY FLOW

IN

ECOSYSTEMS

Energy flows
through an
ecosystem in
one direction
from the sun or
chemical
compounds to
autotrophs
(producers) and
then to various
heterotrophs
(consumers).

Multiple Choice

Which of the following best describes how energy flows through an ecosystem?

• Energy flows in multiple directions, including from consumers to producers.

• Energy flows in one direction, from the sun or chemical compounds to producers and then to consumers.

• Energy only flows from producers to decomposers.

• Energy flows only through plants and not through other organisms.

Food
chains

show how matter
and energy move
through ecosystem
in a series of steps
showing which
organisms transfer
energy by eating
and being eaten.

Multiple Choice

What is a food chain and what does it show in an ecosystem?

• A diagram that shows the types of plants in an ecosystem.

• A sequence that shows how matter and energy move through an ecosystem, illustrating which organisms transfer energy by eating and being eaten.

• A chart that shows how decomposers break down matter in the soil.

• A model that only shows energy flow from producers to the environment.

Each organism in a
food chain represents
a feeding step, or
trophic level, in the
transfer of matter and
energy.

Food
chains

Reorder

Put these in order as they would be on a food chain

• Sunlight

• Plant

• Insect

• Frog

• Snake

1

2

3

4

5

• 1
• 2
• 3
• 4
• 5

Models that show all possible feeding
relationships at each trophic level in a
community; links all food chains in an
ecosystem together.

Food
webs

Open Ended

What is one difference between food chains and food webs

Diagram that shows
amounts of energy
or matter at each
trophic level; three
different types:

Biological
pyramid

Snake
10 kcal

Mice

100 kcal

Insects

1000 kcal

Producers
10, 000 kcal

ENERGY PYRAMID

Fox
(10)

Birds
(25)

Grasshoppers

(250)

Grasses
(3000)

PYRAMID OF NUMBERS

80 g

Human

800 g

Chicken

8000 g
Grain

BIOMASS PYRAMID

Multiple Choice

What do biological pyramids represent in an ecosystem?

• The number of different species in an ecosystem.

• The flow of energy and the relative biomass or number of organisms at each trophic level.

• The types of organisms that make up the ecosystem.

• The geographic distribution of species.