3.3 Exploration 3 (Energy and Matter Distribution in Ecosystems)

pyramid of numbers

A diagram that shows the number of individual organisms at each trophic level in an ecosystem

What happens when trophic levels increase?

As trophic level increases, the amount of available energy is reduced because some is converted to heat or excreted as waste.

Food for thought

Producers convert only about 1 percent of the energy available from sunlight into useable energy.

Food for thought

The amount of energy and biomass decreases in a biomass pyramid as you move up the trophic levels.

Pyramid models

The same pattern of energy and biomass distribution at the organism level also occurs at the ecosystem level.

How to determine left over energy

To determine the amount of energy left for the caterpillar to use, subtract the amount converted to heat and excreted as waste from the total amount consumed: 1000 J - 500 J - 320 J = 180 J The caterpillar has 180 J left over to convert into biomass.

Energy Pyramids

Trophic efficiency is the percentage of energy transferred from one trophic level to the next. Remember that energy transfer from one organism to another is not efficient.

Loss of available energy

When a consumer eats food, the energy it contains undergoes a transformation. Some energy is used for cellular respiration, which provides energy for movement and maintenance of the organism.

biomass pyramid definition

a diagram that compares the biomass of different trophic levels within an ecosystem

energy pyramid definition

diagram that compares energy used by producers, primary consumers, and other trophic levels

Where do ecosystems get their energy?

sunlight

Biomass

total dry mass of all organisms in a given area