Matter & Energy Flow in Ecosystems
Aligned to 5-LS2 — Next Generation Science Standards.
What this lesson teaches
Energy from the sun enters ecosystems through plants (producers). It flows to consumers that eat them, and decomposers break down dead matter, recycling nutrients back to the soil.
Worked examples
Example 1
Grass (producer) → grasshopper → frog → snake. Each arrow shows energy moving. When the snake dies, decomposers return its nutrients to the soil for new grass.
Example 2
Algae → small fish → seal → orca. The ocean has food chains too, and they also start with something that captures sunlight.
Example 3
Energy shrinks at each step. It takes a huge amount of grass to support one hawk, which is why top predators are always rare.
Practice questions
- Build a food chain with four links and label producer/consumer.
- What role do decomposers play?
- What happens to the chain if all the producers disappear?
Watch the lesson
Every lesson comes with a video taught in English and Spanish — the same video the QR code in the printed workbook opens.
▶ Watch this lessonEn español
Flujo de Materia y Energía en los Ecosistemas
La energía del sol entra a los ecosistemas a través de las plantas (productores). Fluye hacia los consumidores que se las comen, y los descomponedores desintegran la materia muerta, reciclando nutrientes de vuelta al suelo.
Ejemplo 1: Pasto (productor) → chapulín → rana → serpiente. Cada flecha muestra cómo se mueve la energía. Cuando la serpiente muere, los descomponedores regresan sus nutrientes al suelo para que crezca nuevo pasto.
Ejemplo 2: Algas → peces pequeños → foca → orca. El océano también tiene cadenas alimenticias, y también empiezan con algo que captura luz solar.
Ejemplo 3: La energía se reduce en cada paso. Se necesita muchísimo pasto para mantener a un solo halcón, por eso los depredadores tope siempre son escasos.
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