B4 Flashcards
What is an ecosystem?
An ecosystem is a community of living organisms interacting with each other and their physical environment.
Define “biotic” and “abiotic” factors in an ecosystem.
Biotic factors are living elements (like plants and animals), while abiotic factors are non-living components (like water, light, and temperature).
What is biodiversity, and why is it important?
Biodiversity is the variety of different species within an ecosystem. It’s important because it increases resilience to environmental changes.
What is a food chain?
A food chain shows the linear flow of energy between organisms, starting from a producer and ending with a top consumer.
Explain the role of decomposers in an ecosystem.
Decomposers break down dead organisms, recycling nutrients back into the ecosystem.
What is nitrogen fixation?
Nitrogen fixation is the process where nitrogen gas is converted into ammonia by bacteria, making nitrogen usable for plants.
What role do decomposers play in the nitrogen cycle?
Decomposers break down dead matter, returning nitrogen to the soil as ammonia.
What is denitrification?
Denitrification is the conversion of nitrates back into nitrogen gas by bacteria, releasing nitrogen into the atmosphere.
What is biomass?
Biomass is the total mass of living material in an organism or ecosystem, representing stored energy.
Why does biomass decrease at each level in a food chain?
Biomass decreases because energy is lost at each trophic level through respiration, heat, and waste.
What does a pyramid of biomass show?
A pyramid of biomass shows the amount of biomass at each trophic level. The thickness represents biomass, which is largest at the base (producers) and decreases toward the top (top consumers) as energy is lost at each level.
