AQA GCSE Biology Ecology: Adaptations, Food Chains, Cycles & Human Impact

What is the definition of a species?

A group of individuals that can interbreed and produce fertile offspring.

What is a habitat?

The natural environment in which a species lives.

Define a population.

A group of individuals of the same species living in a specific area.

What is a community in ecological terms?

A group of different populations that interact in the same habitat.

What is an ecosystem?

The interaction of a community with the non-living (abiotic) parts of the environment.

What is interdependence in ecology?

The reliance of organisms on each other for vital services such as food and shelter.

What can happen when a species is removed from a community?

It can greatly affect the populations of other species by altering predator or prey numbers.

What is a stable community?

A community where biotic and abiotic factors are in balance, resulting in constant population sizes.

What is an abiotic factor?

A non-living factor that can affect a community, such as light, temperature, and moisture levels.

How does light intensity affect plant growth?

Light is required for photosynthesis, which affects the rate of plant growth.

What role does temperature play in ecosystems?

Temperature affects the rate of photosynthesis and the survival of organisms.

Why are moisture levels important for organisms?

Both plants and animals need water to survive.

What is a biotic factor?

A living factor that can affect a community, such as food availability and competition.

How does food availability impact population sizes?

More food allows organisms to breed more successfully, increasing population numbers.

What is an adaptation?

A characteristic that enhances an organism's ability to survive in its environment.

What are structural adaptations?

Physical features of an organism that enhance its survival, such as sharp teeth or camouflage.

What are behavioral adaptations?

Actions organisms take to survive, such as playing dead or basking in the sun.

What are functional adaptations?

Internal processes that help organisms survive, such as water conservation or reproduction methods.

What are extremophiles?

Organisms that live in extreme environments, such as high temperatures or pressures.

What is a producer in an ecosystem?

An organism that produces its own food through photosynthesis, such as plants or algae.

What is a primary consumer?

An organism that eats producers, transferring energy in the ecosystem.

What tools are used to study species distribution in ecosystems?

Transects and quadrats are used to collect and analyze data on species distribution.

What is the carbon cycle?

The process by which carbon is cycled through the environment, including photosynthesis and respiration.

What is the water cycle?

The continuous movement of water through evaporation, condensation, and precipitation.

What happens to predator and prey populations in a stable community?

Their populations cycle; an increase in prey leads to an increase in predators, and vice versa.

What process removes CO2 from the air?

Photosynthesis by green plants and algae.

How is CO2 returned to the atmosphere?

Through respiration of plants, algae, animals, and the combustion of wood and fossil fuels.

What is the role of decomposers in the carbon cycle?

Decomposers break down dead organisms and waste, returning CO2 to the air.

What initiates the water cycle?

The sun's energy causes water to evaporate from seas and lakes.

What is transpiration?

The process by which water vapour is released from plants.

What happens to water vapour in the atmosphere?

It rises and condenses to form clouds.

How does precipitation contribute to the water cycle?

Water returns to the land as rain, snow, or hail, which then runs into lakes and seas.

What factors affect the rate of decomposition?

Temperature, water availability, and oxygen availability.

What is compost?

A natural fertilizer produced from decayed biological material.

How does increased oxygen availability affect composting?

It allows decomposers to respire aerobically, producing heat and speeding up decay.

What is methane gas and how is it produced?

Methane gas is produced by microorganisms decomposing waste anaerobically.

What are biogas generators used for?

To produce methane gas for fuel.

What is the impact of temperature on decay?

Higher temperatures can increase the rate of decay until enzymes denature at too high temperatures.

How does climate change affect species distribution?

It may cause insects and other species to migrate to cooler areas.

What is biodiversity?

The variety of different species of organisms in an ecosystem.

Why is high biodiversity important?

It stabilizes ecosystems and reduces dependency among species.

What human activities negatively impact biodiversity?

Habitat destruction, pollution, and overuse of resources.

What is deforestation?

The large-scale cutting down of trees for land use.

What are the consequences of deforestation?

Increased CO2 emissions, reduced habitats, and decreased biodiversity.

What causes global warming?

The increase of greenhouse gases like CO2 and methane in the atmosphere.

What are some effects of global warming?

Melting ice caps, rising sea levels, and extinction of species.

How can humans positively interact with ecosystems?

By maintaining rainforests and ensuring habitats are not destroyed.

What is the significance of maintaining biodiversity for humans?

It is crucial for food security and the development of new medicines.

What is the role of temperature in decomposition?

Temperature affects the speed of chemical reactions and enzyme activity in decomposers.

What happens to peat bogs when they are drained?

They lose their habitat value and release CO2 into the atmosphere.

What is the relationship between biodiversity and ecosystem stability?

High biodiversity contributes to a more stable and resilient ecosystem.

What is the impact of pollution on ecosystems?

Pollution can kill plants and animals, disrupting food chains and habitats.

What gases are primarily responsible for global warming?

Carbon dioxide and methane

What are the consequences of increased temperatures due to global warming?

Melting ice caps, rising sea levels, altered species migration, and extinction of organisms

What is one positive human interaction with ecosystems?

Maintaining rainforests to ensure habitats are not destroyed

What is one negative human interaction with ecosystems?

Production of greenhouse gases leading to global warming

What are breeding programs aimed at?

Stopping endangered species from becoming extinct

What is the purpose of protecting rare habitats?

To prevent species from becoming extinct and to regenerate damaged habitats

What is the role of decomposers in an ecosystem?

They break down dead plant and animal matter, returning nutrients to the soil

What are the four trophic levels in a food chain?

Producers, primary consumers, secondary consumers, tertiary consumers

What do producers do in an ecosystem?

They make their own food through photosynthesis

What is an apex predator?

A tertiary consumer that has no predators

What does a pyramid of biomass represent?

The relative biomass at each trophic level in an ecosystem

How much biomass is typically transferred to the next trophic level?

Approximately 10%

What is food security?

Having sufficient food to feed the population

What factors affect food security?

Increasing birth rates, changing diets, new pests, climate change, and conflicts

What is one method farmers use to increase efficiency in livestock production?

Raising animals in small cages to reduce movement and energy waste

What are fishing quotas?

Limits on the number of a species of fish that can be caught to prevent overfishing

What is mycoprotein?

A protein-rich food source produced by the fungus Fusarium, suitable for vegetarians

How does genetically modified bacteria help in medicine?

It produces insulin for treating diabetes

What is the benefit of genetically modifying crops?

To increase yields and nutritional value, and to make them resistant to pests

What is the impact of recycling on food production?

It reduces landfill use and conserves natural resources

What happens to biomass that is not converted into the next trophic level?

It is lost as waste, such as faeces or not digested

What is the significance of field margins in agriculture?

They provide habitats for organisms and maintain biodiversity

What is acid rain and how is it caused?

Rain that is acidic due to sulfur dioxide emissions from factories

What is the effect of climate change on food production?

It can lead to crop failures due to altered rainfall patterns

What is the relationship between biodiversity and ecosystem health?

Higher biodiversity generally indicates a healthier ecosystem

What is one consequence of habitat destruction?

Loss of species and reduction in biodiversity

What is the primary role of primary consumers in an ecosystem?

They are herbivores that eat plants

Why is interspecific competition more intense than infraspecific competition?

Interspecific-between the same species so the same things

Interspecific-between different species with different needs