ECO3 Flashcards
(18 cards)
Sun’s Radiant Energy
Only 1–2% is captured by photosynthesis; the rest is reflected or absorbed.
Albedo
The reflectivity of a surface. Snow has high albedo; oceans and forests have low albedo.
Open System (Energy)
Earth receives energy from the Sun and releases it as heat.
Closed System (Matter)
Matter cycles within Earth; it does not leave the system.
Cycling of Matter
Decomposers break down dead material, recycling elements like C, N, and P.
Autotrophs
Producers; make their own food (e.g., plants, algae).
Heterotrophs
Consumers; eat other organisms for energy.
Photoautotrophs
Use light energy for photosynthesis.
Chemoautotrophs
Use energy from chemical reactions (e.g., H₂S in deep sea vents).
Chemosynthesis
Bacteria use chemicals (not sunlight) to make food.
Food Chain
A linear path of energy transfer in an ecosystem.
Food Web
A complex system of interconnected food chains.
Trophic Level
A feeding step in a food chain (e.g., producer, primary consumer).
Rule of 10
Only ~10% of energy is passed to the next trophic level.
Ecological Pyramid
A model that shows trophic level data (number, biomass, energy).
Pyramid of Numbers
Shows number of organisms at each level; can be inverted.
Pyramid of Biomass
Shows dry mass at each level; may be inverted in oceans.
Pyramid of Energy
Always upright; shows total energy flow at each trophic level.
