Photosynthesis is a chemical reaction that uses carbon dioxide, water, and energy (sun) to produce oxygen and glucose.

Photosynthesis is the process used by producers (autotrophs) to provide energy for themselves and consumers (heterotrophs) in an ecosystem.

Cellular respiration is a chemical reaction that uses glucose and oxygen to produce carbon dioxide, water, and energy (ATP).

Cellular respiration is the process used by all organisms (plants and animals) to break down the energy (glucose) provided through photosynthesis.

The reactants of one reaction are the products of the other as matter is not created nor destroyed based on the Law of Conservation of Matter.

Energy is not cycled in an ecosystem; matter is cycled in an ecosystem. Energy is transferred in ecosystems as one organism eats or is eaten by another organism.

Ecosystems are made up of food chains and food webs.

When one organism eats another, typically 10% of the available energy is passed on. The other 90% is used or released as heat.

Organisms at the top of the food chain get the least amount of energy from the original source.

If an organism in a food chain or food web is removed, the predator and prey of that organism may be negatively affected.

Energy is neither created nor destroyed (Law of Conservation of Energy).

The key source of energy comes from the sun.

Matter is cycled through an ecosystem, but energy is not cycled.

Energy is just transferred through the ecosystem and changes form.

Only 10% of energy is transferred from level to level.

90% of energy is lost as heat

Each trophic level depends or is affected by the other

Producers and consumers make up both food chains and food webs

Food webs are more realistic than food chains

Photosynthesis and cellular respiration are interdependent of each other

Both photosynthesis and cellular respiration are chemical reactions and transform energy