IGCSE Biology – Human Influences on the Environment

Vocabulary flashcards covering key terms from the IGCSE Biology ‘Human Influences on the Environment’ lecture, organised to span food production, habitat destruction, pollution, and conservation topics.

Intensive Food Production

Use of modern technology and practices to maximise food yield from limited land and resources.

Agricultural Machinery

Farm equipment that replaces human labour and allows cultivation of much larger areas, improving efficiency.

Chemical Fertilisers

Substances added to soil to supply nutrients, increasing plant growth and crop yield.

Insecticides

Chemicals that kill insect pests, reducing crop damage but potentially harming non-target species and causing pollution.

Herbicides

Chemicals that destroy weeds, lowering competition with crops and increasing yields.

Selective Breeding

Choosing parents with desirable traits to produce offspring with consistently high yields.

Monoculture

Cultivation of a single crop species over a large area, lowering biodiversity and often boosting pest numbers.

Biodiversity

The variety of different species living in a particular area; high levels support stable ecosystems.

Habitat Destruction

Loss or degradation of natural environments, usually through human activities such as farming, building and mining.

Deforestation

Large-scale removal of trees, often unsustainably, leading to species loss, soil erosion, flooding and higher CO₂ levels.

Soil Erosion

Wearing away of topsoil when vegetation is removed, increasing flood and landslide risk.

Leaching

Washing out of soil nutrients into waterways after vegetation removal.

Extinction

Permanent loss of a species when its last members die out.

Pollution

Introduction of harmful substances or energy into land, air or water environments.

Untreated Sewage

Human waste released without purification, adding organic matter that triggers eutrophication.

Chemical Waste

Industrial pollutants such as heavy metals that can bioaccumulate and poison food chains.

Bioaccumulation

Gradual build-up of persistent chemicals in organisms higher up a food chain.

Eutrophication

Nutrient enrichment of water bodies causing algal blooms, oxygen depletion and aquatic death.

Plastic Pollution

Environmental accumulation of non-biodegradable plastics that harm wildlife and release toxins.

Acid Rain

Rainwater made acidic by dissolved sulfur trioxide formed from sulfur dioxide emissions.

Greenhouse Gas

Gas that traps heat in Earth’s atmosphere, e.g., carbon dioxide and methane.

Carbon Dioxide (CO₂)

Major greenhouse gas produced by fossil-fuel combustion and deforestation.

Methane (CH₄)

Powerful greenhouse gas emitted by cattle, rice paddies, landfills and thawing permafrost.

Greenhouse Effect

Natural process where greenhouse gases absorb and re-radiate heat, warming Earth.

Enhanced Greenhouse Effect

Extra warming caused by increased greenhouse gas concentrations from human activities.

Sustainable Resource

Resource produced as fast as it is used, so it does not run out (e.g., timber from managed forests).

Non-renewable Resource

Finite resource that cannot be replaced once used, such as fossil fuels.

Recycling

Processing waste materials (paper, glass, metal, plastic) into new products, saving raw materials and energy.

Forest Stewardship Council (FSC)

Certification body that promotes sustainable forest management and tracks timber products.

Fish Stock Management

Controls to maintain fish populations at sustainable levels.

Quota

Legally set limit on the amount of a particular fish species that can be caught.

Bycatch

Non-target species unintentionally caught during fishing; reducing it makes fishing more sustainable.

Endangered Species

Species at serious risk of extinction in the wild.

Captive Breeding Programme

Conservation strategy breeding endangered species in zoos or sanctuaries to boost numbers.

Seed Bank

Long-term storage of seeds from different plant species to preserve genetic diversity.

Conservation

Protection and management of ecosystems and species to maintain biodiversity and resources.

Artificial Insemination (AI)

Technique inserting semen into females without mating, increasing offspring numbers in conservation breeding.

In Vitro Fertilisation (IVF)

Fertilising gametes in the laboratory to produce embryos for conservation or agriculture.

Genetic Variation

Differences in DNA among individuals; essential for species’ adaptability and survival.

Sustainable Forestry

Managing forests by replanting and monitoring logging to ensure continuous timber supply.

Restocking

Raising young fish or animals for release to replenish wild populations.

Quota Size Limits

Regulations that specify minimum sizes of fish that may be landed to allow juveniles to mature.

Bottom Trawling

Fishing method dragging nets along the seabed, often damaging habitats; restrictions improve sustainability.

Nitrates

Key ions in fertilisers that can run off into water and trigger eutrophication.

Persistent Organic Pollutant (POP)

Chemical (e.g., some pesticides) that resists breakdown and accumulates in ecosystems.

Climate Change

Long-term alteration of temperature and weather patterns due largely to elevated greenhouse gases.

Quaternary Consumers

Top predators in food chains that are most affected by bioaccumulation of toxins.

Sustainable Fishing Gear

Equipment such as minimum-mesh nets or mid-water trawls designed to reduce habitat damage and bycatch.

Education Programmes (Conservation)

Initiatives that inform public and industry about sustainable practices and biodiversity importance.