All flashcards
Flashcard 1: Identify energy at tertiary consumers if producers have 20,000 kJ and transfers are 10% each step.
Answer: 20 kJ. Three 10% transfers: 20,000×0.13=20.
Flashcard 2: Which is larger in most ecosystems: energy in producers or energy in tertiary consumers?
Answer: Energy in producers. Producers have much more energy due to the 10% rule.
Flashcard 3: Which type of consumer typically has higher trophic efficiency: herbivore or carnivore?
Answer: Carnivore (animal tissue is generally more digestible than plant tissue). Animal tissues are more digestible than tough plant cell walls.
Flashcard 4: What is one biological reason plant-based trophic transfers are often less efficient?
Answer: Plant cell walls (cellulose/lignin) reduce digestibility. Cellulose and lignin are difficult to digest and reduce efficiency.
Flashcard 5: Which concept explains why top predators are fewer in number than producers?
Answer: Energy decreases at each trophic level, limiting population size. Less available energy supports smaller populations at higher levels.
Flashcard 6: What is a food chain in terms of energy transfer?
Answer: A linear pathway of energy transfer through feeding relationships. Shows single pathway of who eats whom in sequence.
Flashcard 7: Calculate energy at the next level: producers have 10,000 kJ; use the 10% rule.
Answer: 1,000 kJ. Apply the 10% transfer rule: 10,000×0.1=1,000.
Flashcard 8: What term describes the total mass of living tissue at a trophic level?
Answer: Biomass. Total dry weight of living organisms at a trophic level.
Flashcard 9: Which trophic level contains secondary consumers?
Answer: The level that eats primary consumers. Carnivores that feed on herbivores (primary consumers).
Flashcard 10: What is gross primary productivity (GPP) in an ecosystem?
Answer: Total energy captured by producers via photosynthesis. All energy captured before any is used for producer metabolism.
Flashcard 11: What is net primary productivity (NPP) in terms of energy available to consumers?
Answer: Energy stored in producer biomass available to the next trophic level. Energy remaining after producers use some for their own respiration.
Flashcard 12: What form does most lost energy take as it moves through trophic levels?
Answer: Heat (thermal energy). Energy dissipates as heat during cellular respiration.
Flashcard 13: Which process is the main reason energy is lost between trophic levels?
Answer: Cellular respiration releasing energy as heat. Metabolic processes convert chemical energy to heat energy.
Flashcard 14: Which is larger in most ecosystems: biomass of producers or biomass of secondary consumers?
Answer: Biomass of producers. Producers support all other levels and have the greatest biomass.
Flashcard 15: Which is larger in most ecosystems: energy in producers or energy in tertiary consumers?
Answer: Energy in producers. Producers have much more energy due to the 10% rule.
Flashcard 16: What term describes organisms that feed on detritus (dead organic matter) directly?
Answer: Detritivores. Organisms that consume dead organic matter as their food source.
Flashcard 17: What happens to energy stored in dead organisms and waste products?
Answer: It can be used by decomposers and detritivores, with heat released by respiration. Decomposers extract remaining energy, releasing heat through respiration.
Flashcard 18: Identify the correct direction of energy flow in a food chain.
Answer: From producers to consumers to decomposers, with heat lost at each step. Energy always flows from lower to higher trophic levels.
Flashcard 19: What is the minimum trophic level count in a food chain that includes producers and herbivores?
Answer: Two trophic levels (producers and primary consumers). Producers form the base, herbivores are the second level.
Flashcard 20: What is a food web in terms of energy transfer?
Answer: A network of interconnected food chains showing multiple energy pathways. Multiple interconnected chains showing complex feeding relationships.
Flashcard 21: Which type of consumer typically has higher trophic efficiency: herbivore or carnivore?
Answer: Carnivore (animal tissue is generally more digestible than plant tissue). Animal tissues are more digestible than tough plant cell walls.
Flashcard 22: What is one biological reason plant-based trophic transfers are often less efficient?
Answer: Plant cell walls (cellulose/lignin) reduce digestibility. Cellulose and lignin are difficult to digest and reduce efficiency.
Flashcard 23: Which concept explains why top predators are fewer in number than producers?
Answer: Energy decreases at each trophic level, limiting population size. Less available energy supports smaller populations at higher levels.
Flashcard 24: What is a trophic level in an ecosystem energy pyramid?
Answer: A feeding position that shows energy flow through a food chain/web. Represents an organism's position in the energy flow hierarchy.
Flashcard 25: What is the primary energy source for most terrestrial food webs?
Answer: Solar energy captured by producers via photosynthesis. Sunlight drives photosynthesis, the foundation of most food webs.
Flashcard 26: What term describes organisms that convert light energy into chemical energy?
Answer: Producers (autotrophs). They make their own food using light energy and CO2.
Flashcard 27: What term describes organisms that obtain energy by consuming other organisms?
Answer: Consumers (heterotrophs). They cannot produce their own food and must eat other organisms.
Flashcard 28: What is the typical fraction of energy transferred from one trophic level to the next?
Answer: About 10%. Most energy is lost as heat during metabolic processes.
Flashcard 29: What is the name of the guideline that about 10% of energy passes to the next level?
Answer: The 10% rule (ecological efficiency guideline). A general guideline for energy transfer efficiency in ecosystems.
Flashcard 30: What is a food chain in terms of energy transfer?
Answer: A linear pathway of energy transfer through feeding relationships. Shows single pathway of who eats whom in sequence.