Download Energy Flow

Topic:
Energy Flow
Name: ____________________________
Date:_________________________
Objective: SWBAT understand how energy flows through an ecosystem.
Questions/Main Ideas:
What is Ecology?
Ecology= study of interactions among organisms and between organisms and their
environment
Interdependence= Organisms depend upon each other for survival, such as food,
shelter, Reproduction, Protection
Ex) Predator- prey relationship (lions and zebras)
What is necessary for a
habitat?
Habitat= The area where an organism lives. (Includes both biotic and abiotic
factors)
a. Biotic= living organisms in an environment
Ex) predators, food sources, and competitors
b. Abiotic= nonliving factors in an organism’s environment
Ex) sunlight, pH, temperature, precipitation, salinity, soil, air, etc
Niche= the role a species plays in a community
Ex) How it meets its needs for food, shelter, reproduction,
etc.
What is the main source
of energy on earth?
Energy Flow
The sun is the main energy source for life on Earth.
What is the difference
between an autotroph
and a heterotroph?
1. Autotrophs (Producers)= capture energy from sunlight or chemicals and
produce their own food.
a. photosynthesis= the process of using solar energy to produce food (Ex:
plants).
b. chemosynthesis= the process of using inorganic compounds or chemicals
to produce food (Ex: sulfur bacteria near hydrothermal vents).
Autotrophs are the foundation of all ecosystems because they make energy for all
the other organisms.
2. Heterotrophs (Consumers)= organisms that get their energy from consuming
other organisms.
a. herbivores= eat only plants (cows, deer, rabbits, grasshoppers)
b. carnivores= eat animals (lions, hyenas, wolves).
c. omnivores= eat both plants and animals (humans, bears, crows).
d. detritivores (scavengers)= feed on plant/ animal remains and other dead
matter
(mites, snails, crabs)
e. decomposers= break down organic matter (bacteria and fungi).
Without detritivores and decomposers the entire biosphere (Earth) will be littered
with dead organisms (nature’s garbage men).
What is the 10% Rule?
10% Rule= Only 10 % of the energy flows from one level to the next level
- As energy flows from one level to the next, a large part (90%) is lost
through heat and work done by
organisms.
How do Ecologists
model energy flow?
Ecological Models
1. Food Chain= show the one way flow of
energy in an ecosystem
- the arrow always points in the direction
the energy is going
- sun or inorganic chemicals → autotrophs
→ heterotrophs
- Trophic level= each step of the food
chain (autotroph is first trophic level)
2. Food Web= Food Webs are models
representing the interconnected food
chains in which energy flows.
3. Ecological Pyramids= show
the decreasing amounts of
energy, living matter
(biomass) or number of
organisms at successive
trophic levels.
Summary: