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Northern IrelandBiology

Ecology and the Environment

5 dot points across 5 inquiry questions. Click any dot point for a focused answer with worked past exam questions where available.

How are organisms organised into ecosystems, and how do they depend on each other?

The terms population, community, habitat and ecosystem, the difference between producers, consumers and decomposers, food chains and food webs, and the interdependence of organisms including predator and prey relationships.
A focused CCEA GCSE Biology answer on ecological relationships, covering the terms population, community, habitat and ecosystem, producers, consumers and decomposers, food chains and webs, and interdependence including predator and prey relationships.
8 min answer →

How does energy flow through an ecosystem, and why are food chains short?

How energy from the Sun flows through food chains, why energy is lost at each trophic level, pyramids of numbers and biomass, and calculating the efficiency of energy transfer between trophic levels.
A focused CCEA GCSE Biology answer on energy flow, covering how energy from the Sun flows through food chains, why energy is lost at each trophic level, pyramids of numbers and biomass, and calculating energy transfer efficiency.
8 min answer →

How do humans affect the environment, and how can we reduce the damage?

The causes and effects of pollution including water and air pollution, the use of indicator species to monitor pollution, the consequences of habitat destruction and deforestation, and conservation measures to protect biodiversity.
A focused CCEA GCSE Biology answer on human impact, covering the causes and effects of water and air pollution, indicator species, habitat destruction and deforestation, and conservation measures to protect biodiversity.
8 min answer →

How are carbon and nitrogen recycled through ecosystems?

The carbon cycle including photosynthesis, respiration, combustion and decomposition, and the nitrogen cycle including the roles of decomposers and nitrogen-fixing, nitrifying and denitrifying bacteria.
A focused CCEA GCSE Biology answer on nutrient cycles, covering the carbon cycle through photosynthesis, respiration, combustion and decomposition, and the nitrogen cycle including the roles of the different bacteria.
8 min answer →

How do scientists sample and measure the organisms living in a habitat?

Using quadrats to estimate abundance and percentage cover, using transects to study how distribution changes across a habitat, the meaning of biodiversity, and calculating means and population estimates from sampling data.
A focused CCEA GCSE Biology answer on sampling and biodiversity, covering quadrats for abundance and percentage cover, transects for distribution, the meaning of biodiversity, and calculating means and population estimates from sampling data.
8 min answer →