Unit 7: Ecology
Left Side
Pg # Right Side
Pg #
Unit Page
34
Table of Contents
35
Levels of Organization
36
C.N. – Ecology Part 1
37
Sources of Energy Tree Map
38
C.N. – Energy Flow
39
Food Chain Activity
40
Food Chain/Web Worksheet
41
Energy Flow
Unit 7: Ecology
Chapter 3-2
Energy

The relationship
between organisms
interaction with
their environment is
based on energy
needs

The SUN is the main
energy source for
life on Earth
Producers

Autotrophs: capture energy from
sunlight or chemicals and use it to
make their own food

Because they make their own food,
they are also called PRODUCERS

Ex: plants, bacteria, algae

Two ways producers make their own
food
 Photosynthesis: autotrophs use
light energy (sun) to make food
6CO2 + 6H2O  C6H1206 + 6O2

Carbon dioxide + water  carbohydrates + oxygen
During photosynthesis, Sugar (C6H12O6 )
is produced inside the chloroplasts by
combining Carbon Dioxide (CO2) and
Water (H2O).
CO2 + H2O + light energy  C6H12O6 +
O2
C
O2
O
2 well. At night,
Plants need oxygen as
respiration occurs. Respiration is a
process by which the plant releases
carbon dioxide and lets oxygen into its
cells.
Legend
(CO2)
Carbon dioxide
Oxygen (O2)
Water (H20)
Light energy
The plant combines water and
carbon dioxide to form sugar. The
water is taken up by the plants
root.
Energy from
sunlight is used
by the
chloroplasts to
produce sugar.
Carbon dioxide
enters the
plant through
the stomata.
The plant produces oxygen
during photosynthesis. The
oxygen gas escapes through
the stomata.
 Chemosynthesis:
autotrophs
convert energy stored in
inorganic compounds into food
Ex: bacteria
http://www.pmel.noaa.gov/vents/nemo/education/curr_p1_12.html
Consumers
 Heterotrophs:
rely on other
organisms for their energy and
food supply
 Because they eat other
organisms, they are CONSUMERS

EX: animals, fungi, & insects
Autotroph of Heterotroph?
Palm tree
 Tree Frog
 Black Bear
 Phytoplankton (Energy from sun)
 Grass
 Wild mushroom


5 Types of consumers
 1. Herbivore: eats plants
 a) Ex: rabbit
 2. Carnivore: eats meat
 a) Ex: fox
 3. Omnivore: eats both meat & plants
 a) Ex: Bear
 4.
Detritivore: eat plant/animal
remains or dead matter
a) Ex: earthworms or snails
 5. Decomposer: breaks down
organic matter
a) Ex: bacteria or fungi
Which type of heterotroph?
Tree snake (Eats mice, frogs, insects)
 Sea urchin (Eats seaweed)
 People
 Mushroom (Dead plants and animals)

Feeding Relationships
 How
energy travels through an
ecosystem.
 Food
Chain: diagram showing the
transfer of energy from one
organisms eating another.

EX: Algae is eaten by krill, krill is
eaten by cod, cod is eaten by seal,
seal is eaten by killer whale
 Food
Web: the combination of
ALL possible food chains in an
ecosystem
Grazing & Detrital Food Webs
Identify one food chain in this food
web. Share it with your partner!
Trophic Levels

Trophic Level: (feeding
level) Each step in a food
chain or web.
 First Trophic Level:
 producer / autotroph
 Second Trophic Level:
 Primary consumer
/herbivore
Third Trophic Level:
 Secondary Consumer
 carnivore or omnivore
 Forth Trophic Level:
 Tertiary Consumer
 carnivore or omnivore

Can you identify the trophic level?
Which trophic
level is the krill?
 Which trophic
level is the
leopard seal?
 Which trophic
level is the
algae?

Energy Pyramid

Energy pyramid: a diagram that
shows the amount of energy in
each trophic level of a food chain
or web
 Only 10% of the energy at one
trophic level is transferred to
the next level
 The rest of the energy is lost
as HEAT
The result is that
there must be many
more producers
than consumers
Pair Share

Why are there many more producers than
consumers? How much energy gets
passed from one trophic level to the next?
Biomass Pyramids
Diagram that shows the
amount (in grams) of
potential food available
for each trophic level
 Because of the loss of
energy at each trophic
level, there is usually a
larger mass of living
tissue at the lower levels
than at the upper levels
