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Flashcards in Life On Earth Deck (52)
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What is an Abiotic factor?

Refers to a physical (non-living) factor that affects an ecosystem eg temperature, light intensity, pH etc


What is an adaptation?

A feature of an organism that helps it survive eg thick, hollow fur for insulation in Polar Bears


What is an algal bloom?

A rapid growth in population of algae in ponds/lakes caused by an increase in inorganic nutrients from fertilisers.


What is an allele?

A particular form of a gene.


Where is ammonia found in the Nitrogen cycle?

After death and decomposition and before nitrite.


What is bio accumulation?

Build up of toxic substance in an organism because it is hard to break down. Toxin absorb from the environment or thought food.


The definition of biodiversity.

It is the number and abundance of different species within an ecosystem.


What is a biological control?

A natural control of pests using natural predators, parasites or disease.


What is a biome and what can influence there distribution?

A biome is a region of the plant with characteristic climate, plants and animals. It is influenced by temperature and rainfall.


What is a Biotic factor?

A biological (living) factor that affects an ecosystem eg predication or competition.


What is a carnivore?

A consumer that gets its energy from eating other animals.


What is the definition of a community?

All the populations of different species living in a habitat.


What is intraspecific competition?

Competition for resources between individuals of the SAME species.


What is interspecific competition?

Competition for resources which occurs between individuals of DIFFERENT species.


What is the more severe form of competition intraspecific or interspecific?

Intraspecific because because the requirements for individuals are identical.


What is a consumer?

An organism which gets its energy by feeding on other organisms.


What is a decomposer? Name one.

A decomposer is an organism involved in the breakdown of dead organic material and waste. Examples are bacteria or fungi.


Definition of deforestation?

Large scale removal of trees from an area.


What do denitrifying bacteria do?

They convert nitrates in the soil into nitrogen gas, which is released into the atmosphere.


What is desertification?

The process by which arid land becomes desert. May be a result of climate change.


What is an ecosystem?

An ecological system consisting of a habitat and it's community of organisms.


What is evolution?

The change in inherited characteristics of an organisms from generation to generation. It leads to gradual change in the characteristics of a species and the divergence into a new species.


What is a fertiliser?

A chemical added to soil to improve plant growth and crop yield. Contains nitrogen, potassium and phosphorus.


What is a food chain?

A linear sequence of organisms showing the feeding relationship between them. Starts with a producer and ends in the top predator.


What does Genetically Modified (GM) mean?

An organism/cell that has had its genetic code altered by the addition of a gene from another organism. Gives it a new characteristic.


What is a habitat?

An area in which a population of organisms live.


What is habitat destruction?

Human destruction of natural habitat by activities such as deforestation/over grazing.


What is a herbivore?

An animal that gets its energy by eating plants.


What is an indicator species?

Organisms (eg lichen) that by the presence, abundance or absence give information such as pollution levels in the environment


What is a monoculture?

Large scale growing of a single crop. Good economic benefits due to large yields BUT can cause soil depletion and disease.