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All 22 Flashcards — Biomass
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Question
Define biomass.
Answer
Biomass is the total dry mass of living organisms in a given area, representing stored chemical energy at a trophic level.
💡 Hint
Dry mass in an area
Question
Define ecological pyramids.
Answer
Ecological pyramids are diagrams that represent trophic levels using numbers, biomass, or energy, with producers at the base.
💡 Hint
Numbers, biomass, energy
Question
Define a pyramid of numbers.
Answer
A pyramid of numbers shows the number of individual organisms at each trophic level.
💡 Hint
Counts individuals
Question
Define a pyramid of biomass.
Answer
A pyramid of biomass shows the total dry mass of organisms at each trophic level.
💡 Hint
Dry mass per level
Question
Define a pyramid of energy.
Answer
A pyramid of energy shows energy flow per unit area per unit time at each trophic level.
💡 Hint
Energy flow rate
Question
Define biomass.
Answer
Biomass is the total dry mass of living organisms in a given area, representing stored chemical energy at a trophic level.
💡 Hint
Dry mass in an area
Question
Define ecological pyramids.
Answer
Ecological pyramids are diagrams that represent trophic levels using numbers, biomass, or energy, with producers at the base.
💡 Hint
Numbers, biomass, energy
Question
Define a pyramid of numbers.
Answer
A pyramid of numbers shows the number of individual organisms at each trophic level.
💡 Hint
Counts individuals
Question
Define a pyramid of biomass.
Answer
A pyramid of biomass shows the total dry mass of organisms at each trophic level.
💡 Hint
Dry mass per level
Question
Define a pyramid of energy.
Answer
A pyramid of energy shows energy flow per unit area per unit time at each trophic level.
💡 Hint
Energy flow rate
Question
Why is a pyramid of energy always upright?
Answer
Energy is lost as heat at every trophic transfer, so less energy is available at higher levels.
💡 Hint
Heat loss
Question
Why can a pyramid of numbers be inverted?
Answer
One large producer, such as a tree, can support many consumers like insects, making the level above wider.
💡 Hint
One supports many
Question
Explain why biomass is measured as dry mass rather than fresh mass.
Answer
Water content varies widely and does not contain usable chemical energy, so drying allows fair comparison of stored energy between organisms and trophic levels.
💡 Hint
Water varies; no usable energy
Question
Explain why biomass is measured as dry mass rather than fresh mass.
Answer
Water content varies widely and does not contain usable chemical energy, so drying allows fair comparison of stored energy between organisms and trophic levels.
💡 Hint
Water varies; no usable energy
Question
Why is a pyramid of energy always upright?
Answer
Energy is lost as heat at every trophic transfer, so less energy is available at higher levels.
💡 Hint
Heat loss
Question
Why are producers always at the base of ecological pyramids?
Answer
Producers capture incoming energy, usually sunlight, and convert it into biomass that supports all higher trophic levels.
💡 Hint
Energy enters at producers
Question
Why can biomass pyramids be inverted in aquatic ecosystems?
Answer
Producers like phytoplankton have low standing biomass but reproduce rapidly, supporting larger consumer biomass.
💡 Hint
Fast turnover
Question
Why can biomass pyramids be inverted in aquatic ecosystems?
Answer
Producers like phytoplankton have low standing biomass but reproduce rapidly, supporting larger consumer biomass.
💡 Hint
Fast turnover
Question
Why are producers always at the base of ecological pyramids?
Answer
Producers capture incoming energy, usually sunlight, and convert it into biomass that supports all higher trophic levels.
💡 Hint
Energy enters at producers
Question
Why can a pyramid of numbers be inverted?
Answer
One large producer, such as a tree, can support many consumers like insects, making the level above wider.
💡 Hint
One supports many
Question
What general trend do ecological pyramids show?
Answer
They show that numbers, biomass, and available energy usually decrease at higher trophic levels.
💡 Hint
Less higher up
Question
What general trend do ecological pyramids show?
Answer
They show that numbers, biomass, and available energy usually decrease at higher trophic levels.
💡 Hint
Less higher up
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Topic 2.5 hub
Flows of energy and matter
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