Edexcel A Level Biology: Ecosystems & Energy Transfer

Vocabulary flashcards covering key ecological terms, biotic and abiotic factors, sampling techniques, succession, and energy productivity for Edexcel A Level Biology.

Habitat

The place where an organism lives.

Microhabitat

A small habitat within a larger area, such as an individual tree.

Habitat Specialist

A species that can only survive in a very specific type of habitat.

Generalist

A species that can survive in a range of different habitats.

Population

All of the individuals of one species living in a habitat.

Abundance

The number of individuals of a particular species living in a habitat, representing population size.

Distribution

The exact location of a population or species within a habitat.

Community

Multiple populations of different species living and interacting in the same area.

Ecosystem

A community and its interactions with the non-living (abiotic) parts of its habitat.

Biotic Factor

A living factor that influences populations within their community, such as food availability, new predators, new pathogens, or competition.

Abiotic Factor

A non-living factor that influences populations within their community, such as light intensity, temperature, moisture levels, soil pH, or salinity.

Niche

The specific role of a species within its habitat, including what it eats, where it lives and feeds, and when it is active.

Random Sampling

A sampling method where sample points are selected randomly to eliminate investigator bias.

Systematic Sampling

A sampling method where sample points are located at fixed intervals throughout a site, often along a transect.

Transect

A line laid out across a site along an environmental gradient to measure changes in species abundance and distribution.

Frame Quadrat

A square frame placed in a sample area to measure the presence, frequency, percentage cover, or abundance of sessile organisms.

ACFOR Scale

A qualitative scale used to measure species abundance as Abundant, Common, Frequent, Occasional, Rare, or None.

Point Quadrat

A vertical frame with holes through which pins are lowered to measure the presence or percentage cover of species in dense vegetation.

Kite Diagram

A graph visually representing both the distribution and abundance of species, as well as changes in abiotic factors, along a transect.

Succession

The dynamic process of ecosystem change over time, involving changes in biotic and abiotic conditions.

Primary Succession

The process of ecosystem change over time occurring on newly formed or newly exposed land where no soil initially exists.

Colonisation

The arrival of organisms on bare land during the initial stages of succession.

Pioneer Species

The first species (such as mosses and lichens) to colonise bare land, adapted to withstand harsh conditions with low nutrients and water.

Climax Community

The final, stable community formed at the end of succession containing complex plant and animal species.

Secondary Succession

Succession occurring on previously occupied land where soil is already present, such as after a wildfire or deforestation.

Plagioclimax

A stable climax community that develops and is maintained as a result of human intervention preventing natural succession.

Gross Primary Productivity (GPP)

The rate at which light energy is converted into chemical energy and stored as carbohydrates during photosynthesis by producers.

Net Primary Productivity (NPP)

The rate at which energy is stored in plant biomass and made available to primary consumers, calculated as $NPP = GPP - R$.

Net Productivity

The rate at which energy is stored and converted into biomass in the body of a consumer after energy losses from respiration and waste.