1Define extinction.
The permanent loss of all members of a species.
2List three causes of extinction.
Habitat loss, over-hunting, and climate change.
3What is the enhanced greenhouse effect?
Global warming caused by human-produced greenhouse gases trapping more heat.
4List three greenhouse gases.
Carbon dioxide, methane, and water vapour.
5What are planetary boundaries?
Safe operating limits for human activity to prevent irreversible environmental damage.
6Which planetary boundary has been crossed?
Biodiversity (biosphere integrity) or the nitrogen cycle.
7What is monoculture?
The cultivation of a single crop over a large area.
8List a disadvantage of monoculture.
It reduces biodiversity and makes crops more vulnerable to pests and disease.
9Define deforestation.
The large-scale removal of trees from an area.
10How does deforestation affect the carbon cycle?
It reduces carbon dioxide uptake by photosynthesis and increases carbon dioxide release through burning or decay.
11What is overfishing?
Catching fish at a rate faster than they can reproduce.
12What are planetary aerosols?
Microscopic particles in the atmosphere that can reflect sunlight or cause respiratory problems.
13Define conservation.
The protection and management of ecosystems and species to maintain biodiversity.
14What is an SSSI?
A Site of Special Scientific Interest.
15What is the land use boundary?
The limit to how much land can be converted for human use, such as farming.
16Define ocean acidification.
The decrease in the pH of the Earth’s oceans caused by the uptake of carbon dioxide.
17What is the impact of ocean acidification?
It removes calcium carbonate from shells and corals, making them weaker.
18What are novel entities?
Man-made pollutants such as microplastics and nanomaterials.
19What is desalination?
The removal of salt from seawater to produce fresh water.
20List a method of conserving fish stocks.
Fishing quotas, mesh size regulations, or marine protected areas.
21What is the ozone boundary?
The limit to the depletion of the stratospheric ozone layer.
22Why is the nitrogen cycle boundary a concern?
Excessive fertiliser use causes eutrophication and dead zones.
23What is planetary resilience?
The Earth’s ability to recover from environmental disturbances.
24How does climate change affect species distribution?
Habitats shift, often towards the poles, causing species to migrate or die out.
25What is ecotourism?
Responsible travel to natural areas that conserves the environment and supports local people.
26Define sustainability.
Meeting present needs without compromising the ability of future generations to meet theirs.
27What is the role of seed banks?
To preserve plant genetic diversity for the future.
28How do hedgerows support biodiversity?
They provide habitats, food sources, and wildlife corridors for movement.
29What is intensive farming?
Farming that uses high inputs such as fertilisers and pesticides to maximise yield.
30What is the freshwater boundary?
The limit to the amount of renewable freshwater that humans can use.