The variety of all different species of organisms on Earth, or within a particular ecosystem. Includes the range of different habitats and genetic variation within species.

What is eutrophication and what causes it?

Eutrophication is when excess nutrients (from fertiliser or sewage run-off) enter water. This causes rapid algae growth, blocking sunlight to underwater plants. When algae die and decompose, oxygen is used up, killing aquatic organisms.

Exam questions for Biodiversity and Human Impacts

What is the best definition of biodiversity?

A. The total number of individual organisms in an ecosystem
B. The variety of all different species of organisms on Earth or within a particular ecosystem
C. The process by which species adapt to their environment over time
D. The number of plants found in a habitat

1 markfoundation

Explain why deforestation leads to a reduction in biodiversity.

3 marksstandard

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