37.21 Nitrogen Cycle

Question 1

How is Nitrogen Cycle cycled

Answer 1

nitrogen gas

Question 2

Chemical formula of nitrogen gas

Answer 2

N2

Question 3

What is nitrogen a limiting factor of

Answer 3

plants

Question 4

What molecules are nitrogen important ingredients of

Answer 4

proteins and nucleic acids

Question 5

How many abiotic reservoirs does nitrogen have

Answer 5

2

Question 6

What are the 2 abiotic reservoirs of nitrogen

Answer 6

the atmosphere and soil

Question 7

Is nitrogen cycled globally or locally

Answer 7

both because its abiotic reservoirs are soil and the atmosphere

Question 8

How much of the atmosphere is nitrogen

Answer 8

80%

Question 9

Can plants absorb nitrogen in its N2 form

Answer 9

no

Question 10

Nitrogen Fixation

Answer 10

the conversion of atmospheric nitrogen (N2) to nitrogen compounds (NH4+ and NO3-) that plants can absorb and use

Question 11

What organism does nitrogen fixation

Answer 11

bacteria

Question 12

Can animals use N2 in its N2 form

Answer 12

no

Question 13

What kind of atom is N2

Answer 13

a diatomic atom

Question 14

Diatomic Atom

Answer 14

an atom that always pairs with at least itself and is never found alone

Question 15

How many steps does the nitrogen cycle have

Answer 15

8

Question 16

What is the first step of the nitrogen cycle

Answer 16

Nitrogen Fixing Bacteria that live symbiotically in the root nodules of some species of plants supply their hosts with a usable source of nitrogen

Question 17

Legumes

Answer 17

the largest group of plants that has this mutualistic relationship with bacteria which supplies them with a usable source of nitrogen

Question 18

What is the second step of the nitrogen cycle

Answer 18

Nitrogen-fixing bacteria converts N2 to ammonia, which then picks up another H+ to become ammonium .

Question 19

Chemical formula of ammonia

Answer 19

NH3

Question 20

Chemical formula of ammonium

Answer 20

NH4+

Question 21

What is the third step of the nitrogen cycle

Answer 21

Nitrifying bacteria in the soil convert some of the NH4+ to nitrites and then into nitrates which is more easily usable by plants

Question 22

What form of nitrogen is usable by plants

Answer 22

nitrates

Question 23

Chemical Formula for nitrates

Answer 23

NO3-

Question 24

Chemical Formula for nitrites

Answer 24

NO2-

Question 25

Are nitrites usable by plants

Answer 25

no

Question 26

What is the 4th step of the nitrogen cycle

Answer 26

Plants use the nitrate to synthesize molecules such as amino acids, which make proteins and nucleic acids which make nucleotides

Question 27

What is the 5th step of the nitrogen cycle

Answer 27

Herbivores eat plants and digest the proteins to build the protein it needs
Carnivores and omnivores gain nitrogen from their prey and do the same thing as the herbivores

Question 28

Despite the losing of nitrogen in step 5 what else happens?

Answer 28

Nitrogen containing waste products are also made during metabolism

Question 29

Where is nitrogen-fixing bacteria found

Answer 29

in soil, lagoons, and bean plants

Question 30

What is the 6th step of the nitrogen cycle

Answer 30

Organisms that are not consumed eventually die and become detritus which is decomposed by prokaryotes and fungi. Decomposition releases NH4+ from organic compounds back into the soil, replenishing the soil reservoir of NH4+

Question 31

What happens to the NH4+ created during decomposition after it goes back into the soil

Answer 31

it goes back to the nitrogen fixing bacteria and nitrifying bacteria (Goes back into the cycle that was earlier in the nitrogen cycle)

Question 32

What is the last step of the nitrogen cycle

Answer 32

Denitrifying Bacteria strip the oxygen from NO3-, releasing N2 back into the atmosphere in low oxygen conditions

Question 33

What is dentrifying bacteria aka

Answer 33

Dentrifiers

Question 34

What is the cycle of how nitrogen cycles chemically

Answer 34

N2 –> NH3 –> (NH4+) –> (N02-) –> (NO3-) –> (NH4+) –> (NO2-) –> (NO3-) –> Ns

Question 35

How do human activities also disrupt the nitrogen cycle

Answer 35

by adding more nitrogen than what is added by natural processes by combustion of fossil fuels and coal power plants which produce nitrogen oxides

Question 36

Nitrogen Oxides

Answer 36

NO and N2

Question 37

Outside of the nitrogen cycle how are some NH4+ and NO3-

Answer 37

in the atmosphere by chemical reactions including N2 and ammonia