Transfers of Energy and Matter
these are question and answer:
Ecosystems and Energy Flow
Q: What is ecology? A: The study of relationships between living organisms and their environment, including biotic and abiotic factors.
Q: Define ecosystem. A: A community of organisms and their surroundings, including biotic and abiotic factors, which interact with each other.
Q: Are ecosystems open or closed systems? A: Ecosystems are open systems because energy and matter can enter and exit.
Q: What is the principal source of energy for most ecosystems? A: Sunlight, except for ecosystems relying on hydrogen sulfide (H2S) instead.
Biotic and Abiotic Factors
Q: What are biotic factors? A: Living components of an ecosystem, like animals, plants, and microorganisms.
Q: What are abiotic factors? A: Non-living components of an ecosystem, such as water, soil, and temperature.
Species and Populations
Q: Define species. A: Groups of organisms that can potentially interbreed to produce fertile offspring.
Q: What is a population? A: All individuals of a species living in the same area at the same time.
Q: How does reproductive isolation affect evolution? A: It can lead to the development of new species over time.
Food Chains and Webs
Q: What is a food chain? A: A sequence of organisms through which energy flows via feeding relationships.
Q: What is biomass? A: The total dry mass of organisms in an ecosystem.
Q: Define producer. A: An organism that uses light or chemical energy to create its own food (e.g., plants).
Q: What is the role of consumers in a food chain? A: They feed on producers or other consumers, transferring energy through the chain.
Q: What do the arrows in a food chain represent? A: The flow of energy from one organism to the next.
Trophic Levels and Energy Loss
Q: Define trophic level. A: The position of an organism in a food chain, indicating its feeding relationship to others.
Q: What percentage of energy is passed to the next trophic level? A: About 10% of the energy is passed to the next level.
Q: Why is there energy loss between trophic levels? A: Due to heat loss from cellular respiration and organic matter not consumed.
Q: What limits the number of trophic levels in an ecosystem? A: Energy losses at each trophic level reduce the available energy for higher levels.
Autotrophs and Heterotrophs
Q: Define autotroph. A: An organism that produces its own food from inorganic substances, using light or chemical energy.
Q: What is carbon fixation? A: The process by which autotrophs convert inorganic carbon (CO2) into organic compounds.
Q: Define heterotroph. A: An organism that obtains organic carbon compounds from other organisms.
Q: What is the role of detritivores and saprotrophs in ecosystems? A: They break down dead organic matter, recycling nutrients back into the ecosystem.
Primary and Secondary Production
Q: Define primary production. A: The accumulation of carbon compounds in biomass by autotrophs.
Q: What is secondary production? A: The accumulation of biomass by heterotrophs from consuming other organisms.
Q: How is net primary production (NPP) calculated? A: NPP = Gross Primary Production (GPP) - Respiration (R).
Carbon Cycle and Climate
Q: What is a carbon sink? A: An environment that absorbs more CO2 from the atmosphere than it releases (e.g., forests, oceans).
Q: What is a carbon source? A: A process or environment that releases more CO2 into the atmosphere than it absorbs (e.g., burning fossil fuels).
Q: What is the Keeling Curve? A: A graph showing the concentration of CO2 in Earth’s atmosphere over time.
Q: Define flux in the carbon cycle. A: The movement of carbon atoms through Earth's different environments.