Question

cycle and flow in a freshwater lake ecosystem
the food chain below shows the movement of energy through several organisms in a freshwater lake ecosystem.
freshwater food chain
aquatic plants → caddisfly larva → bluegill fish → largemouth bass fish
drag and drop the numbers into the table to show the energy available at each trophic level of an energy pyramid that contains these four organisms.
energy available
(kilocalories/m²/year)
organism
aquatic plants
caddisfly larva
bluegill fish
largemouth bass fish

Explanation:

Step1: Energy transfer rule

In an energy pyramid, only about 10% of the energy is transferred from one trophic level to the next.

Step2: Assign energy values

• Aquatic plants (producers) have the most energy. So aquatic plants have 1000 kilocalories/m²/year.
• Caddisfly larva (primary consumer) gets 10% of aquatic plants' energy: \(1000\times0.1 = 100\) kilocalories/m²/year.
• Bluegill fish (secondary consumer) gets 10% of caddisfly larva's energy: \(100\times0.1=10\) kilocalories/m²/year.
• Largemouth bass fish (tertiary consumer) gets 10% of bluegill fish's energy: \(10\times0.1 = 1\) kilocalories/m²/year.

Answer:

Organism	Energy Available (kilocalories/m²/year)
Caddisfly larva	100
Bluegill fish	10
Largemouth bass fish	1