1. Community Interactions &
Food Chains, Webs & Pyramids
Chapter 2.2

2. Trophic Level: Who eats who in the food chain
Steps along which materials & energy pass
Shown as food chains, webs & pyramids

3. Food Chain:
ONLY ONE source of food
Less stable

4. Food Web: More than one choice of food
Several food chains linked together
More stable

5. Food Pyramid
Tertiary
Secondary
Primary consumer
Producer

6. Food Pyramid
Tertiary
Secondary consumer
Primary consumer
Producer

7. Food Pyramid
Illustrates?
Food Chain
of numbers
of biomass
of energy

8. Food Pyramid activity heat heat activity 90%: Lost as Waste Used for
10% of the energy is passed on as biomass
90%:
Lost as
Waste
Used for
Reproduction
activity
heat
heat
activity

9. Biomagnification Magnification= to increase Concentration of toxins
Are magnified
In upper pyramid levels

10. Biomagnification the top consumer requires more biomass
and concentrates the toxin

11. Food Pyramid
Human
Shark
Bass
Smelt
Algae
Who is most susceptible ?

12. Cycles in Nature:

13. Energy Flows………... Flows in one direction
Will never return to the same form
Conservation of Energy:
Energy changes form
But is never lost

14. Matter cycles………….. Matter can be recycled Matter can be reformed
The basic building blocks are reused
Conservation of Matter

15. Carbon cycle………...

16. Tracing the cycling of matter…..

17. Energy & Matter in an Ecosystem: