4.1.6 nutreint cycling

Question 1

nutrient cycling definitions

Answer 1

process of materials being passed between abiotic and biotic components of an ecosystem

Question 2

how is nitrogen cycled through the ecosystem

Answer 2

-most organisms can only use nitrogen as a compound (nitrate)
-nitrates in soil are taken up by plant roots and are used to make protein.
-when plant is eaten nitrogen compounds are passed on
-when animals and plants die, compounds are broken down and released into soil as ammonia
-nitrogen in soil is also from faeces or urine

Question 3

nitrogen fixing bacteria

Answer 3

convert atmospheric nitrogen gas, which is almost inert, into solid nitrogen compounds that can then be absorbed by plants

Question 4

nitrifying bacteria

Answer 4

convert the most reduced form of soil nitrogen, ammonia, into its most oxidized form, nitrate.

Question 5

denitrifying bacteria

Answer 5

conversion of nitrates in the soil to free atmospheric nitrogen.

Question 6

water cycle

Answer 6

water goes to ocean and evaporates
or
transpiration of water vapour
then
vapour condenses forming clouds
precipitation