Nitrogen Cycle and Bacteria Roles

The video explains the nitrogen cycle, highlighting the conversion of nitrogen gas into usable forms for plants. It covers biological, atmospheric, and industrial fixation processes, detailing the roles of bacteria and natural phenomena like lightning. The video also discusses nitrification, assimilation, denitrification, and decomposition, emphasizing how these processes contribute to the nitrogen cycle and plant nutrition.

What is the primary source of nitrogen for living organisms?

• Nitrogen gas in the atmosphere

• Nitrogen compounds in water

• Nitrogen compounds in rocks

• Nitrogen compounds in the ocean

Which type of bacteria is involved in symbiotic nitrogen fixation?

• Pseudomonas species

• Azotobacter species

• Rhizobium species

• Nitrosomonas species

What natural phenomenon contributes to atmospheric nitrogen fixation?

• Tsunamis

• Volcanic eruptions

• Earthquakes

• Lightning

What is the main product of the Haber process in industrial nitrogen fixation?

• Phosphate

• Nitrate

• Ammonia

• Nitric acid

Which bacteria convert ammonium ions to nitrite ions during nitrification?

• Azotobacter species

• Nitrosomonas species

• Pseudomonas species

• Rhizobium species

What is the role of nitrifying bacteria in the nitrogen cycle?

• Convert nitrogen gas to ammonia

• Convert ammonium ions to nitrates

• Convert nitrates to nitrogen gas

• Convert organic nitrogen to ammonia

How do plants primarily absorb nitrogen?

• Through their stems

• Through their flowers

• Through their roots as nitrates

• Through their leaves

Which process involves the conversion of nitrates back to nitrogen gas?

• Assimilation

• Denitrification

• Fixation

• Nitrification

What role do decomposers play in the nitrogen cycle?

• Convert nitrogen gas to ammonia

• Convert organic nitrogen to ammonia

• Convert nitrates to nitrites

• Convert ammonia to nitrogen gas

Which bacteria are known as denitrifying bacteria?

• Rhizobium species

• Pseudomonas species

• Nitrosomonas species

• Azotobacter species