section15
DESCRIPTION
Ecology Note CardsTRANSCRIPT
Ecosystems
Biology I Factoids
Factoid 256
• Section 15
• An ecosystem is made up of communities and their environments.
Factoid 257
• Producers (autotrophs) make their own food.
Factoid 258
• Consumers (heterotrophs) get their energy by eating autotrophs (producers) or by eating other heterotrophs (consumers).
Factoid 259
• Primary consumers eat producers. Energy is transferred from the producers to the primary consumers. Primary consumers are herbivores.
Factoid 260
• Secondary consumers eat primary consumers. Energy is transferred when one organism eats another.
Factoid 261
• Decomposers break down dead organisms into detritus (organic matter).
Factoid 262
• A food chain is a series of feeding relationships starting with a producer.
Factoid 263
• A food web is a series of overlapping food chains.
Factoid 264
• The trophic level is a feeding level. Every step of a food chain is a trophic level.
Factoid 265
• An energy pyramid shows the energy that is transferred between trophic levels.
Factoid 266
• Only about 10% of the energy at each level is transferred to the next higher level. The rest is used by the organism itself and some is lost as heat.
Factoid 267
• Since only 10% of energy is transferred from one level to another, a food chain usually only has 4 or 5 trophic levels.
Factoid 268
• Biomass is the mass of dry organic materials in an organism.
Factoid 269
• A biomass pyramid indicates the amount of organic material at a given trophic level. Typically producers have the largest biomass.
Factoid 270
• A pyramid of numbers shows the approximate number of individual organisms at each level that an ecosystem can support.
Factoid 271
• The biosphere is all living things on the planet. The biosphere is divided into biomes.
Factoid 272
• Since matter can not be created or destroyed according to the Law of Conservation of Mass, it must be recycled in the environment.
Factoid 273
• The Water Cycle
Factoid 274
• Transpiration is the evaporation of water through the plant.
Factoid 275
• The Carbon-Oxygen Cycle
Factoid 276
• The Nitrogen Cycle
Factoid 277
• Nitrogen fixation is accomplished by bacteria and lightning.
• Denitrification is accomplished by bacteria.
Factoid 278
• The Phosphorus Cycle