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Ecosystems exam Flashcards

Ecosystems exam
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  • Ecosystem
    A community of organisms and their environment, where energy flows and matter cycles.
  • What is the primary source of energy for most ecosystems?
    The sun.
  • Trophic Levels
    The hierarchical levels in an ecosystem, comprising producers, primary consumers, secondary consumers, and tertiary consumers.
  • What role do decomposers play in an ecosystem?
    They recycle matter by breaking down dead organisms and organic waste.
  • Water Cycle
    The continuous movement of water above, on, and below the Earth's surface through processes like evaporation, condensation, and precipitation.
  • What is the efficiency of energy transfer between trophic levels?
    Approximately 10%.
  • Carbon Cycle
    The movement of carbon through the biosphere, involving processes like photosynthesis and cellular respiration.
  • What is Gross Primary Productivity (GPP)?
    The total amount of energy generated by primary producers in an area over time.
  • Net Primary Productivity (NPP)
    The amount of biomass added by primary producers after subtracting the energy used for respiration.
  • What is a limiting factor in aquatic ecosystems?
    Nutrient availability.
  • Biomagnification
    The concentration of toxins in higher trophic levels of a food web.
  • What is the main limiting factor in terrestrial ecosystems?
    Temperature and water availability.
  • Primary Producers
    Organisms that generate biomass from inorganic matter, usually through photosynthesis.
  • What is the role of primary consumers?
    They feed on primary producers.
  • Nitrogen Cycle
    The movement of nitrogen through the biosphere, primarily facilitated by nitrogen-fixing bacteria.
  • What is the significance of the phosphorus cycle?
    It recycles phosphorus locally in ecosystems, mainly from rock and soil.
  • Trophic Cascade
    A process where predators control the population of prey, indirectly affecting the next trophic level.
  • What is secondary production?
    The amount of energy converted to new biomass by heterotrophs.
  • Biogeochemical Cycles
    Pathways by which chemical substances move through both biotic and abiotic components of Earth.
  • What is evapotranspiration?
    The process of water evaporation from plants.
  • Humus
    Completely decayed organic matter in soil, rich in nutrients.
  • What is the role of primary decomposers?
    They feed on dead plant matter and recycle nutrients back into the ecosystem.
  • Food Web
    A complex network of interconnected food chains in an ecosystem.
  • What is the law of conservation of energy?
    Energy cannot be created or destroyed, only transferred or transformed.
  • Photosynthesis
    The process by which primary producers convert carbon dioxide and sunlight into organic matter.
  • What is the water table?
    The level in the ground that is saturated with water.
  • Aquifer
    A porous rock layer that holds groundwater.
  • What is the main reservoir of nitrogen?
    The atmosphere.
  • Sublimation
    The process where a substance transitions from a solid directly to a gas.
  • What is the biosphere?
    The sum of all ecosystems on Earth.