Life Science
Mrs. Volpe
Ecosystems and Biomes
Chapter 22
Flow of Energy in Ecosystems
PRODUCERS are organisms that make their
own food.
CONSUMERS are organisms that obtain
energy by feeding on other organisms.
DECOMPOSERS break down wastes and dead
organisms and return the raw material to the
ecosystem.
The FOOD CHAIN and the FOOD WEB show
the movement of energy through an ecosystem.
A food chain is a series of events in which one
organism eats another and obtains energy.
A food web consists of many overlapping food
chains in an ecosystem.
ENERGY PYRAMIDS show the amount of
energy that moves from on feeding level to
another in the food web.
Water Cycle
The WATER CYCLE is the continuous process
by which water moves from Earth’s surface to
the atmosphere and back. Made up of:
Evaporation – Condensation – Precipitation
Transpiration – Run Off/Collection
Transpiration – The release of water from plant
leaves.
Run Off/Collection –
Surface runoff: Precipitation runoff which
travels over the soil surface to the nearest
stream channel.
Snowmelt runoff to streams: The movement of
water as surface runoff from snow and ice to
surface water.
The Carbon and Oxygen Cycles
CC/Producers take in carbon dioxide
gas from the air during
photosynthesis. They use carbon to
make food molecules, such as sugar
and starch.
OC/Producers release oxygen as a
result of photosynthesis. Most
organisms use this oxygen to carry
out their life processes.
Nitrogen Cycle
Nitrogen moves from the air to the
soil, into living things, and back into
the air.