11-29-16 WARM UP 1. Which organism represents the primary consumer?

2. Which organism represents the secondary consumer?

3. What do the mushrooms and rotting log represent?

ENERGY PYRAMIDS

Food chains do not typically go past 4 or 5 trophic levels

Why?

Energy cannot be created or destroyedEvery time energy is transferred, some of that energy is lost

On average, about 90% of the energy is “lost”- only 10% moves to the next trophic level

WHY ONLY 10%?1. Not everything gets eaten

2. There is still some potential energy in animal waste

3. Each energy conversion releases heat (a type of energy) to the environment

New energy is always being added to the food chain by the Sun

ENERGY PYRAMIDSThey show how energy is lost at each stage of a food web

In an energy pyramid:

•Producers are at the bottom, because they have the most available energy. (They got it right from the source)

The next level is the primary consumers. They got 10% of the energy in the plants.

The next level is the secondary consumers. They got 10% of the energy in the primary consumers.

ENERGY PYRAMID PRACTICE

If there is 10,000 kcal of energy available in the plants at the bottom of the pyramid, how much energy will make it to the zebras, and how much will make it to the lion?

10,000

1000

100

An energy Pyramid

Gets smaller as it goes up since there is less and less energy as you go up

Pyramid of biomass

How much everything weighs at each level

Always pyramid shaped

Pyramid of numbers

How many organisms are at each level

Usually mostly producers, then primary consumers, then secondary and so on

100,000 plants

1000 voles

1 owl

Pyramid of numbers

Could look like this:

1 oak tree supports lots of primary consumers, which support fewer secondary consumers, then even fewer tertiary, etc.

1 oak tree

1000 caterpillars

50 bluetits

1 sparrow hawk

ENERGY PYRAMID ACTIVITY

DIRECTIONS: CUT WHEN FINISHED AND TAPE

WHAT DOES AN ENERGY PYRAMID REPRESENT?

•Use complete sentences

•Write 3 factsCONSTRUCT A TERRESTRIAL ENERGY PYRAMID WITH 4 TROPHIC LEVELS•Draw, Color, Label

CONSTRUCT AN AQUATIC ENERGY PYRAMID WITH 5 TROPHIC LEVELS

•Draw, Color, Label

1.

5.

4.

3.

2.

PLACE ON THE COUNTER

THINK ABOUT YOUR FOOD CHAIN BEFORE MAKING YOUR PYRAMID