Thursday, Septempber 6th
Bellwork:

1. Get your supply bins out of the drawers.

2. Open your workbook to page 21 read this
page and answer the questions.
Life Science
Energy Transfer
Energy Transfer
Each time one organism eats another
organism, energy is transferred.
Animals get their energy from:

Food
Two types of food

1.
2.
Plants
Animals
Plants get their energy from:
 Sunlight
Food Chains are sequences in which energy is
transferred from organism to organism as one
eats another.



They are single line, chain-of-events
The arrow’s direction points in the
direction that energy is being transferred.
The problem with food chains is they
don’t show the relationships
between interdependent organisms.
Food Webs are the feeding relationships
among all organisms in an ecosystem
 Made up of many food chains.
 Shows how all organisms in an ecosystem
are connected.




Each time energy is transferred some energy
is lost as heat.
Not all of the energy is transferred to the
next organism
The bottom level, the producers, have the
largest population and the most amount of
energy.
The highest level has the smallest
population because energy available to
them is limited.




Energy pyramids are often used to show how
energy is transferred from one trophic level
to the next.
As the pyramid narrows at the top, the
amount of energy becomes less.
There are fewer organisms at the top.
Example: Zebras and other herbivores
out-number lions 1,000 to 1
Ecosystems rarely have more than 3-4
trophic levels because of the significant loss
of energy
Food Chain
Killer Whale
Seal
Salmon
Plankton
FRIDAY!!! September
th
7
Bellwork:

1. Grab your supply bins.

2. Complete the Food Web Questions
Worksheet using page 25 in your workbooks.
Food Web
Energy Pyramid
Tertiary consumers, also
known heterotrophs, are animals
Examples include: Hawks, fox
80% of
the
available
energy is
used at
each
level
10%
10%
Secondary consumers, also
known as 2nd order heterotrophs
are animals
Examples include: Robins, mice
Primary consumers, also
known as 1st order heterotrophs
are animals
Examples include: Cows, deer, caterpillars
Producers, also known as autotrophs,
are plants
Example: Trees, grass, wheat
10%
10%
10% of the
energy is
released as
heat at each
level