IGCSE Biology glossary
Population
Biology editorial review is supported by the named review panel. Reviewer participation may vary by guide. Checked against Cambridge IGCSE Biology 0610 (2026–2028); last reviewed August 2026.
Definition
A group of organisms of the same species living in the same area at the same time and able to interbreed. Population size is affected by birth rate, death rate, immigration and emigration.
What to include in an exam answer
A population is ONE species in ONE area. A community is ALL species in ONE area. An ecosystem includes the community plus the abiotic (non-living) factors. Get these three definitions right.
Example in context
Define the term population (1 mark): A group of organisms of the same species living in the same area at the same time.
Related syllabus topic
Organisms & their environment