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Ecosystem

All the living organisms and non-living components in a habitat, and their interactions.

Conservation

Active management of an ecosystem, habitat or resource to maintain biodiversity and natural resources.

Preservation

Leaving ecosystems undisturbed.

Limiting factor

A factor that will limit the rate of reaction when at a suboptimal level.

Oxidation

A reaction requiring the loss of hydrogen or loss of electron.

Photolysis of water

A chemical reaction producing protons, electrons, and oxygen, part of the light-dependent reaction in plants.

Photoionisation

Light excites electrons in the plant’s chlorophyll, leading to electron loss and a positively charged chlorophyll.

Acetylcoenzyme A

A molecule resulting from the combination of acetate and coenzyme A in the link reaction.

Calorimeter

An instrument used to determine the chemical energy store of a known mass of biomass.

Gross primary production

The chemical energy store in plant biomass, in a given area or volume.

Net primary production

The chemical energy store in plant biomass, after respiratory losses to the environment have been accounted for.

Nitrification

The conversion of ammonia into nitrate.

Nitrogen fixation

The conversion of nitrogen into ammonia.

Denitrification

The conversion of nitrate to nitrogen, reducing nitrate supply.

Mutualism

An advantageous, nutritional relationship between two species where both benefit.

Saprobiont

An organism that decomposes proteins externally, releasing ammonia.

Leaching

A process that removes nutrients from the soil by carrying soluble nutrients deeper into the soil.

Stimulus

A change in the internal or external environment.

Receptor

A cell or protein detecting a specific type of stimulus.

Effector

Part of the body producing a response to a detected stimulus, often a muscle or gland.