4.10 describe the stages in the nitrogen cycle, including the roles of nitrogen fixing bacteria, decomposers, nitrifying bacteria and denitryfying bacteria (specific names of bacteria are not required)

Firstly, here's a diagram...



Okay so...

nitrogen fixing bacteria - this turns atmospheric nitrogen into nitrogen compounds (in the soil) that plants can use

decomposers - turns proteins and urea (from plants and animals) into ammonia

nitrifying bacteria - this turns ammonia into nitrates

denitrifying bacteria - this turns nitrates back into atmospheric nitrogen gas

The process repeats.

NOTE: Some of these bacterium live in the soil and some live on the root nodules of plants.

4.9 describe the stages in the carbon cycle, including respiration, photosynthesis, decomposition and combustion

To start, here is a diagram...



Okay so...

Respiration - breathing basically. this releases carbon dioxide back into the air.

Photosynthesis - carbon is taken in (by the plants)

Decomposition - when plants and animals die, decomposers decompose them. this introduces carbon back into the soil

Combustion - things like wood and fossil fuels are burned. This releases carbon dioxide back into the air

The carbon dioxide in the air is then taken in by plants and the cycle continues(this is why plants are so important)

4.8 describe the stages in the water cycle, including evaporation, transpiration, condensation and precipitation

Firstly, here is a diagram...


Okay, so...

Evaporation - this is where water (from  the ground) gets warmed (usually from sunlight). When this happens, the water molecules gain energy and they start to move lots more, eventually they turn into a gas.

Transpiration - all transpiration is is evaporation from plants/leaves

Condensation - When the warm water vapour is carried upwards (convection currents). However, the higher you go the colder it gets. The water vapour eventually cools down and condenses, forming clouds

Precipitation - a fancy name for rain/snow/hail