Conservation — Cambridge IGCSE Combined Science

What endangered and extinct mean, the causes of endangerment and extinction, and how endangered species can be conserved.

Spec B16.2Human influences on ecosystems, subtopic 2 of 2

Revision notes

1 short note, in the order of the specification. Each one in short:

Endangered species and how to conserve them
Endangered species risk dying out through habitat loss, hunting or pollution; captive breeding, seed banks and protected reserves help conserve them.

2 exam-style questions (8 marks), each with its mark scheme.

3 cards: flip them, mark what you knew, and practise the rest.

The whole of human influences on ecosystems on one page, so you can see where this subtopic fits.

Free PDFs to print or save.

Give four reasons why species become endangered or extinct.
Show answer
Any four of: climate change, habitat destruction, hunting, overharvesting, pollution, introduced species.
Supplement What is a seed bank?
Show answer
A store of seeds from rare plants, kept so that the plants can be grown again if wild populations are lost.

Written and checked against the Cambridge IGCSE Combined Science (0653) specification · Updated October 2026