Communities Flashcards – AQA GCSE Biology - Foundation (8461)

What is a population?

A group of organisms of one species living in the same area at the same time.

What is a community in an ecosystem?

All the populations of different species in the ecosystem.

What is an ecosystem?

A community and its environment functioning as an interacting unit.

What does interdependence mean in a community?

Species depend on other species for resources or services.

What are four resources or services for which species may depend on one another?

Food, shelter, pollination and seed dispersal.

How can removing one species affect the wider community?

Changes in species that depend on it can have further effects throughout the community.

What is a stable community?

A community where species and environmental factors are in balance and population sizes remain fairly constant, though they may fluctuate.

When does competition occur between organisms?

When they need the same resource and its supply is limited.

Can competition occur between organisms of the same species, different species, or both?

Both: competition can occur within a species or between different species.

What does competition affect for organisms in a community?

Their access to resources needed for survival and reproduction.

What four resources do plants often compete for?

Light, space, water and mineral ions from the soil.

What three things do animals often compete for?

Food, mates and territory.

Does competition for mates occur within a species or between different species?

Within a species.

What can be used to suggest which resources organisms compete for in a habitat?

The organisms present and the resources available.

How do you extract information about a community from a chart, graph or table?

Identify what the labels, axes, scales or headings represent, including units, then read the relevant values.

How do you interpret community interaction data?

Compare values or patterns and relate them to a possible interaction between organisms. The conclusion must be supported by the data.

Does an association between changes in two populations establish that one caused the other?

No. An association alone does not establish causation.