The Nitrogen Cycle AQA A Level Biology

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the % of nitrogen in the atmosphere

active transport

how is nitrogen absorbed in plants?

roots

the part of the plant which absorbs nitrogen

nitrification

the process of ammonium ions to nitrites (NO2) to nitrates (NO3)

oxidation

type of reaction of nitrification

denitrification

the process of bacteria converting nitrates to atmospheric nitrogen

anaerobic conditions

the conditions of denitrification

waterlogged soil

e.g. of conditions of denitrification

denitrifying bacteria

denitrification is carried out by

nitrogen fixation

process of converting atmospheric nitrogen into nitrogen-containing compounds

mutualistic nitrogen-fixing bacteria

bacteria which live in the nodules of leguminous plants and carry out nitrogen fixation

mutualistic relationship

the relationship between bacteria and leguminous plants where the bacteria give the plants amino acids and the plant gives the bacteria sugar/carbohydrates

pea plants

e.g. of leguminous plants

ammonification

saprobionts feed on dead and waste matter and release ammonia which makes ammonium ions in the soil.

extracellular digestion

the process of saprobionts digesting the dead or waste matter by depositing enzymes

saprobionts

another name for decomposers, e.g. bacteria / fungi