Conservation Flashcards – Cambridge IGCSE (9–1) Biology 0970 (Extended) (2026–2028)

When is a renewable resource used sustainably?

When its rate of removal does not exceed its rate of renewal, so continued use does not cause it to run out.

How can forests be managed sustainably as timber is removed?

Trees must be able to regrow or be replaced as timber is removed.

What must happen for fish stocks to be harvested sustainably?

Fish populations must reproduce sufficiently to replace the fish caught.

When does a species become endangered?

When its risk of extinction increases.

When is a species extinct?

When no individuals of the species remain.

How can climate change threaten a species?

Conditions can change faster than organisms can tolerate them or move to suitable habitats.

How can habitat destruction threaten a species?

It removes the places and resources needed for survival and reproduction.

How can hunting and overharvesting threaten a species?

They can reduce populations faster than they recover.

How can pollution threaten a species?

It can harm organisms or make habitats unsuitable.

What three ways can introduced species threaten native organisms?

Competition, predation and the spread of disease.

How can environmental pressures make a population unable to sustain itself?

They can reduce survival and reproduction until the population can no longer sustain itself.

What is captive breeding of endangered animals?

Breeding individuals in a managed environment to conserve the species.

How can captive breeding support a species whose wild population is too small or threatened to recover reliably?

It produces offspring, increasing numbers and maintaining a population that can support the species’ continued survival.

How do seed banks conserve plant species?

They collect and store viable seeds that can germinate into new plants if a species becomes rare or threatened.

What is an advantage of seed banks over keeping plant material growing continuously?

They conserve plant material without having to keep every plant growing continuously.

How do protected areas help conserve forests?

They restrict activities that damage forests.

What do tree-removal quotas limit?

The number of trees that may be removed.

How does replanting help conserve forests?

It replaces harvested trees so the forest can continue to grow.

How does education support forest conservation?

It encourages people to understand the effects of forest loss and support practices that allow forests to persist.

How can limiting catches help conserve fish stocks?

It gives fish populations opportunities to reproduce.

What is a closed season in fish stock conservation?

A specified period during which fishing is prevented.

How do protected areas help conserve fish stocks?

They restrict fishing in important habitats.

What does a fishing quota limit?

The number of fish caught.

What do controls on net type and mesh size affect?

Which fish are caught.

How can a suitable net mesh size help conserve fish stocks?

It allows smaller fish to escape and grow before capture.

Why are fish catches and populations monitored?

To assess whether conservation controls are effective.

How can education help conserve fish stocks?

It encourages people to follow practices that maintain fish stocks.

What do conservation programmes aim to do to biodiversity?

Maintain or increase it.

What do conservation programmes aim to do to the likelihood of species extinction?

Reduce it.

What does protecting vulnerable ecosystems help preserve?

The organisms and interactions on which those ecosystems depend.

What two types of ecosystem function does conservation help maintain?

Nutrient cycling and the provision of resources, such as food, drugs, fuel and genes.

How does artificial insemination produce offspring in captive breeding?

Sperm is placed in a female’s reproductive tract, allowing fertilisation inside her body.

How does in vitro fertilisation produce offspring in captive breeding?

An egg is fertilised with sperm outside the body, and the resulting embryo is placed in a female to develop.

Why are artificial insemination and in vitro fertilisation useful in captive breeding programmes?

They help selected animals reproduce without natural mating, potentially increasing the number of individuals in an endangered species.

Why can genetic variation decrease when a population becomes small?

Fewer individuals contribute genes to future generations.

What genetic risk increases when close relatives breed in a small population?

Offspring are more likely to inherit harmful characteristics.

Why does reduced genetic variation make a population more vulnerable to disease or environmental change?

There are fewer differences among individuals that might help some survive.

What can the genetic effects of a small population mean for its future?

They make the population more vulnerable to further decline and extinction.