Warm Up: List all of the
components of this ecosystem…
https://www.youtube.com/watch?v=v6ubvEJ3KG
M
Learning Goals and Activities
 Compare and contrast
 PowerPoint
biotic and abiotic
factors in an
ecosystem
 Explain where
organisms get their
energy
 Track energy as it
flows throughout an
ecosystem
 Videos
 Homework: Work on
notes and homework
packet
ECOSYSTEMS: Everything is Connected
Ecosystem: all of the
organisms living together with
their physical environment
Components of an Ecosystem
 In order to survive, ecosystems need 5 components:
1. Energy
2. Mineral nutrients
3. Water
4. Oxygen
5. Living Organisms
Biotic and Abiotic Factors
Biotic
 Living and once-living
Abiotic
 Nonliving
Energy Flow in Ecosystems
What is the ultimate source of
energy for almost all organisms?
Life Depends on the Sun
 Photosynthesis: the process by which
plants, algae and bacteria use sunlight, carbon
dioxide and water to produce carbohydrates
and oxygen.
6CO₂ + 6H₂0 + solar energy
+ 6O₂
C₆H₁₂O₆
From Producers to Consumers
• Producer (autotroph): organism that
makes its own food.
• Consumer (heterotrophs): organisms
that get their energy by eating other
organisms.
Sunlight
Plants
Rabbits
Coyote
Consumers
 Primary, Secondary and Tertiary Consumers
Decomposers and Scavengers
Break down dead organisms and
returns nutrients to soil, water
and air.
Example: Fungi and Bacteria
Scavengers - prevent spread of
diseases
Vultures TED Talks
 The significance of scavengers...
 http://www.ted.com/talks/munir_virani_
why_i_love_vultures.html
Food Chains and Food Webs
Food chains: sequence in which
energy is transferred from one
organism to the next as each organism
eats another organism.
Food web: shows many feeding
relationships that are possible in an
ecosystem.
Food Chains
Food Webs
 Producers?
 Primary
consumers?
 Secondary
consumers?
 Tertiary
consumers?
Identify 1st, 2nd, 3rd and 4th level
consumers in this food web.
18
What type of ecosystems does not
receive their energy from the sun?
http://www.montereyinstitute.org/noaa/lesson05
.html
Deep-Ocean Ecosystems
Chemosynthesis: Bacteria use
hydrogen sulfide from
hydrothermal vents to make their
food.
Other underwater organisms eat
this bacteria.
Exit Ticket
Why might the abundance of
life at hydrothermal vents
support the idea that there is
life beyond Earth?
Trophic Levels and Energy Transfer
Identify 1st, 2nd, 3rd and 4th level
consumers in this food web.
23
Trophic Levels
 Each step in the transfer of energy
through a food web in an ecosystem is a
trophic level.
Trophic Levels
 Each time energy is transferred, some of
the energy is lost as heat and less is
available to organisms at the next tropic
level.
10% Rule
 90% of energy is used for everyday
function
i.e.: body temp., movement
 10% is stored and then transferred to the
consumer.
0.1%
1%
10%
100%
10% rule in action
1 lb of VULTURE
10%
10 lbs of HUMAN
10%
100 lbs of COW
10%
1000 lbs of GRASS
10% rule in action
 What trophic level should the bulk of the biomass be
in an ecosystem? Producers
 Example- The Savanna of Africa
 100 km2 of grasses (10 km x 10 km)
 Herd of 1000 wildebeests
 Pride of 15 lions
 The higher up the food chain, the less available
energy  less top-level consumers
 4th or 5th level consumers are rare in nature
10% Rule
 https://www.youtube.com/watch?v=ScizkxMlEOM