1. Today’s Learning Target(s):. How is energy transferred in an ecosystem
Today’s Learning Target(s): How is energy transferred in an ecosystem? Success Criteria: Students will be able to show and explain three ways energy is transferred through an ecosystem

2. ENERGY PATHS 3 ways to illustrate energy flow
1. Food Chain: Single path
3 ways to illustrate energy flow
3. Energy Pyramid
2. Food Web: many paths

3. Review: Types of Consumers
Herbivore – plant eater
Omnivore – eats plants and meat
Carnivore – eats meat
Decomposer – breaks down dead matter

4. Trophic Levels — each step in a food chain or food web
Consumer Levels – level a consumer in based on it’s TL.
5th Trophic Level- Quaternary Consumers
(carnivore or omnivore)
4th Trophic Level- — Tertiary Consumers
3rd Trophic Level- Secondary Consumers
(carnivores or omnivores)
2nd Trophic Level- Primary Consumers
(herbivores - omnivores)
1st Trophic Level- Producers (autotrophs)

5. ENERGY PYRAMIDS The energy pyramid shows energy flow in an ecosystem:
Top Consumer
Energy stored by
Secondary Consumers
Primary Consumers
ENERGY STORED
BY PRODUCERS
A level of the energy pyramid is called a Trophic Level
Each trophic level represents the energy for those organisms

6. TROPHIC LEVELS Energy is lost at each trophic level
~ 90% is used for life’s processes and/or released environment as heat
~ 10% of the energy is passed on to the next energy level
10% Rule:
Only about 10% of the energy from one level is passed on to the next level

7. ENERGY PYRAMID Life Processes & Heat Life Processes & Heat
Energy Loss in
Heat &
Life Processes:
Breathing, Walking,
Reproducing…
Life Processes
& Heat
Life Processes
& Heat
Light and
Chemical
Energy
Life Processes
& Heat

9. ENERGY FLOW IN ECOSYSTEM

10. ENERGY FLOW IN ECOSYSTEM

11. Energy Transfer
A large number of producers are required to support even a few top level consumers.
tertiary
consumers
500
5,000
secondary
consumers
primary
consumers
50,000
500,000
producers

12. QUICK REVIEW
Practice! If 100% of the energy is available at the first trophic level, what percentages of the energy are available at the second and third trophic levels? 1%
10%
100%

13. QUICK REVIEW! energy pyramid organism Producers 10%
All organisms in an ecosystem need _______ from food to live. An energy ________ shows how much food energy is passed from one ________ to another through food chains. __________ have the largest spot at the base of the pyramid. Altogether, only about _____ of the food energy at each level gets passed up to the next level.
energy
pyramid
organism
Producers
10%