Chapter 2.2

Trophic Level:• Who eats who in the food

chain• Steps along which materials

& energy pass• Shown as food chains, webs &

pyramids

Food Chain:

• ONLY ONE source of food

• Less stable

Food Web:• More than one

choice of food

• Several food chains linked together

• More stable

• Tertiary• Secondary• Primary consumer• Producer

• Tertiary• Secondary consumer• Primary consumer• Producer

Illustrates?

Food Chain

• of numbers

• of biomass

• of energy

10% of the energy is passed on as biomass

90%:• Lost as• Waste • Used for• Reproduction

• Magnification=

to increase

• Concentration of toxins

• Are magnified

• In upper pyramid levels

• the top consumer

• requires more biomass

• and concentrates the toxin

• Human

• Shark

• Bass

• Smelt

• AlgaeWho is most susceptible ?

Cycles in Nature:

Energy Flows………...

• Flows in one direction

• Will never return to the same form

• Conservation of Energy:

• Energy changes form

• But is never lost

Matter cycles…………..• Matter can be

recycled• Matter can be

reformed• The basic building

blocks are reused• Conservation of

Matter

Carbon cycle………...

Tracing the cycling of matter…..

Energy & Matter in an Ecosystem: