Transcript Energy Flow in Ecosystems

Photosynthesis
Chlorophyll
• The cells in leaves contain chlorophyll
• Traps energy from the sun to produce energyrich sugar molecules--carbohydrates
6CO2 + 6H2O + solar energy = C6H12O6 + 6O2
Energy & Nutrient Transfer
Producer
• Organism that makes
its own food
• Also called autorophs
Consumer
• Organism that get
their energy by eating
other organisms.
• Also called
heterotrophs
Decomposers
• Organisms that feeds
by breaking down
organic matter from
dead organisms
• Examples: bacteria
and fungi
Exception to the Rule
• Deep-Ocean Ecosystems
--Tube worms depend on bacteria that live
inside them to survive. The bacteria uses
energy from Hydrogen Sulfide to make
their own food
chemosynthesis
Chemosynthesis
Life Depends on the Sun
• Organisms use energy to move, grow and
reproduce
Grizzly Bears
Omnivore—eats both meat & plants
Can eat up to 1.5% of their body weight in one day
when eating salmon and 33% of body weight
when eating fruits & vegetation.
• How many pounds of salmon
can a 200lb grizzly bear eat in
one day?
15% of 200 = 30lbs
• How many pounds of fruits and
vegetation can the same bear
eat in one day?
33% of 200 = 66 lbs
Cellular Respiration
Breaking down of food
to yield energy using
the O2 you breath in
C6H12O6 + 6O2 =
6CO2 + 6H20 + energy
Excess Energy
• Stored as Fat or Sugar
Energy Transfer
• Food Chains, Food Webs, Trophic Levels
Food Chain
• Sequence in which
energy is transferred
from one organism to
the next as each
organism eats
another organism
Food Web
• Feeding
Relationships that are
possible in an
ecosystem
Who Eats Who-Energy Transfer
Food Chain – Food Web
Trophic Level
• Each step in the
transfer of energy
through a food chain
or web in an
ecosystem
Food Pyramid
Energy Loss Affects
• 1. decrease amount of energy impacts
each trophic level
• 2. Loss limits the number of trophic levels;
rarely have 4 or 5 levels since so much
energy is needed to support
Trophic Cascade
• Indirect interaction
between predators
and the resources
consumed by the
predator’s prey
Cycling of Materials
• Materials in an ecosystem are constantly
reused in an endless cycle
Nitrogen & Carbon Cycle
Nitrogen Cycle
Movement of Nitrogen between atmosphere,
bacteria and other organisms
Phosphorus Cycle
Movement of phosphorus from the
environment to organisms and back
Aquatic Ecosystem
How Ecosystems Change
• Primary Succession
occurs on a surface
where no ecosystem
existed before
• Secondary Succession
occurs where an
ecosystem previously
existed—pioneer species,
climax community
Primary Succession
Ecological Succession
Old Field Succession