Threats to Biodiversity
Habitat loss and fragmentation, overexploitation, invasive species, pollution, climate change, small populations and conservation responses.
How to study Higher Biology
Move from accurate biological mechanisms to unfamiliar data, experimental evidence and justified conclusions. Use current official materials for the written, extended-response and controlled-assignment formats that this question bank does not reproduce.
Core concepts
Concept 1
Trace direct and interacting threats from human activity to population and ecosystem change.
Exam cue: Trace direct and interacting threats from human activity to population and ecosystem change.
Concept 2
Explain how fragmentation, small population size and low genetic diversity increase extinction risk.
Exam cue: Explain how fragmentation, small population size and low genetic diversity increase extinction risk.
Concept 3
Evaluate habitat protection, restoration, connectivity, captive breeding, reintroduction and genetic monitoring.
Exam cue: Evaluate habitat protection, restoration, connectivity, captive breeding, reintroduction and genetic monitoring.
Risk pitfalls and guardrails
A corridor can improve gene flow but may also spread disease or invasive species.
Guardrail: Check vocabulary, sequence, direction, compartment, units and whether the evidence supports causation or only an association.
Population recovery is not secure if habitat causes and genetic risks remain unaddressed.
Guardrail: Check vocabulary, sequence, direction, compartment, units and whether the evidence supports causation or only an association.
Memory anchors
Threat set
Habitat, harvest, invaders, pollution and climate.
Recovery plan
Protect habitat, reconnect populations, monitor genes and numbers.
Checkpoint rule
Do the check-up only after you can summarize each concept in one sentence and identify one dangerous pitfall from memory.
Knowledge Check (after reading)
Short check-up to confirm understanding of this module.
Check-up Questions
How can heavy exploitation reduce a population's genetic diversity?
What is the bottleneck effect?
Answer all questions to submit.
Next step personalized recommendations
Continue learning
Move forward only after this module is stable.
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