Big Idea: Matter and energy flow through an ecosystem. 


  • Ecosystems: An ecosystem is a community of interacting organisms and their physical environments
  • Organism: Living plants and animals
  • Matter: has mass, takes up space, made of molecules
    • Examples: solids (chair, tree, grass, human, bear), liquids (water, orange juice, milk), gas (air, oxygen) 
    • Flows in a cycle: starts as nutrients in the soil, moves through organisms, returns to the soil after death by decomposers 
  • Energy: Causes matter to move or change 
    • Examples: stored energy, thermal/heat energy, kinetic/movement energy, light energy, sound energy, elecrtical energy
  • Photosythesis: plants use light energy from the sun, water, air, and nutrients from the soil to make sugar/glucose. The sugar is stored in the leaves, stem and roots. The sugar molecules have stored energy and are broken down and used as the plant needs. *see steps below  
  • Decompoers: organisms that break down dead plants and animals and use their energy and matter
    • Examples: worms, bacterial, mushrooms/fungi, insects such as beetles, ants, termits and more
  • Organic matter: plant and animal matterial 
  • Original source of energy: sunlight
  • Original source of matter: nutrients in soil, air, water= NAW 
  • Food web: Track the energy and matter from the original source> plant/producer> animal(s)/consumer> decomposer
    • Matter returns to the soil from the decomposer
  • Producer: plant that makes its 'food' (food= sugar) using matter and energy from its original source
  • Consumer: gets its matter and energy from producers and other consumers


Organisms need energy for 5 things:

  • Growth
  • Body repair
  • Movement
  • Reproduction
  • Body Warmth 

Organisms need matter for 2 things:

  • Growth
  • Reproduction 


  1. Roots absorb water and nutrients from the soil. 
  2. The water and nutrients transfer from the roots to the leaves. 
  3. The leaves absorb air/carbon dioxide and sunlight through pores. 
  4. The leaves use the energy from the sun to combine the air, water and nutrients. 
    1. air+water+nutrients+ energy= sugar molecule with stored energy
  5. The plant stores the sugar molecules in the roots, leaves, and stem. 
  6. The plant breaks down the suagr molecule to use the stored energy for body repair, growth, and reproduction.

The stored energy and matter in the plant is use by animals. Consumers (animals that eat other plants and animals) eat the plant and use its energy and matter for body repair (matter/energy), growth (matter/energy), reproduction (matter/energy), movement (kinetic energy) and body warmth (heat energy). The matter and energy moves from animal to animal. When the animals die, decomposers break them down to use the matter and energy. Organic matter is added back into the soil from the dead organisms and decompoers. The organic matter adds nutrients to the soil. Plants abosorb the nutrients in the soil through their roots to use for photosynthesis, and the process begins again. 


Image result for photosynthesis diagram


A food chain is a way to track energy and matter by what an animal eats. Multiple food chains in an ecosystem are called a food web. 




Image result for food chain



A food chain will always start with a producer/plant. The plant uses energy from the sun and matter from the nutrients, water and air to make sugar. This sugar is full of stored energy. The stored energy is passed from the producer to a consumer. The consumer either uses the stored energy and matter for life's processes (growth, reproduction, body warmth, body repair, and movement) or is eaten by another consumer. The stored energy and matter are passed from producer to consumer, to consumer until eventually it gets to a decomposer. The decomposer breaks down the organism and returns plant and animal material (organic matter) to the soil. 

Extra Resources:

Watch videos from Khan Academy here