For self-assessment questions, with exercises and discussions, just click on the correct topic at Biology GCSE & IGCSE Question Bank. The s-cool revision site lets you revise the topic, summarizes the topic & tests you on it. Skoool gives you a lesson, including progress questions, for each Biology topic but you’ll need sound on for it.
Topic 21 revision notes in downloadable word format; to be completed.
This powerpoint covers a lot of Topic 21, as well as revising a lot of Topic 19:
Igcse biology edexcel 4.1 4.17 from Marcos Rodriguez
Science in Focus – The Human Impact – a 19m video.
21.1 Food Supply
A work in progress!
21.2 Habitat Destruction
21.3 Pollution
WATER POLLUTION
EUTROPHICATION
Eutrophication – a short video from The Virtual School:
A lesson (how sewage kills fish) from Mr Dare:
PLASTICS
What really happens to the plastic you throw away:
The Great Pacific Ocean Garbage Patch:
ENHANCED GREENHOUSE EFFECT & CLIMATE CHANGE
A lesson on the Enhanced Greenhouse Effect from Mr Dare:
Mr W sings Seven ways to reduce carbon.
ACID RAIN
A lesson on Acid Rain from Mr Dare:
Here’s a short (less than 5 minute) video clip from BBC iScience – Acid Rain.
21.4 Conservation
A work in progress!