IB biology 4: ecology

Define ecology

The study of the environment and how organisms interact with it

Define community

Populations of different species living alongside each other and interacting with each other

Define population

A group of organisms belonging to the same species inhabiting the same area at the same time

Define species

A group of organisms that can potentially interbreed to produce fertile offspring

Define ecosystem

A community and its abiotic environment

Define biome

A biogeographical unit defined by the types of organisms present (eg. aquatic biome may contain marine ecosystems)

Define biosphere

The region of the Earth’s surface and atmosphere that is inhabited by living things

Define habitat

The environment in which a species usually lives

Define niche

The match of a species to a specific environmental condition

Define consumer

A heterotroph that feeds on other organisms via ingestion

Define producer

An organism that synthesizes its own biomass from sunlight for other organisms to feed on

Define autotroph

An organism (such as most plants) which creates its own biomass/energy, normally from sunlight

Define heterotroph

An organism that obtains its biomass/energy from ingesting other organisms

Define saprotroph

A heterotroph that obtains organic nutrients from dead organisms by external digestion (such as bracket fungus)

Define detritivore

A heterotroph that obtains organic nutrients from detritus by internal digestion (such as woodlice)

What is the difference between a decomposer and a detritivore?

• Decomposers include bacteria and fungi

• Detritivores are larger organisms such as earthworms and woodlice

What is a carnivore?

An organism that eats animals/meat

What is a herbivore?

An organism that eats plants

What is an omnivore?

An organism that eats plants and animals

What is a specialist feeder?

An organism that only eats one thing (eg. giant pandas eating only bamboo)

What is a generalist feeder?

An organism that eats many different types of foods (eg. urban foxes scavenging)

What is a mesocosm?

A small-scale investigation

Self-sustaining ecosystems

They provide sufficient biological complexity compared to the natural environment being modelled but allow more variables being controlled

How do carbon compounds in dead organic matter become methane?

Anaerobic conversion by methanogenic Archaeans

Which domain do methanogenic bacteria belong to?

Archaea

Name the process by which organic compounds in autotrophs are transferred to heterotrophs

Feeding

What does oxidation do to atmospheric methane?

It turns it into water and carbon dioxide in the atmosphere