Microbiology and Nitrogen Cycle

Nitrosomonas is a genus of bacteria that oxidizes ammonia into nitrites, which is the first step of the nitrification process.

Azospirillum is a nitrogen-fixing bacterium that lives in the rhizosphere and forms a loose association with the roots of grasses and cereal crops.

Anabaena is a genus of filamentous cyanobacteria that is capable of nitrogen fixation, often found in symbiotic associations with plants like Azolla.

Nif genes (nitrogen fixation genes) have been transferred to various bacteria to enhance their nitrogen-fixing capabilities, including both Rhizobium and Bradyrhizobium species.

Azotobacter is a free-living, non-symbiotic nitrogen-fixing bacterium, whereas Rhizobium, VAM, and Anabaena are typically associated with symbiotic relationships.

Bacillus subtilis is well-documented as a phosphate-solubilizing bacterium that helps convert insoluble phosphorus into forms available for plant uptake.

Some amount of phosphour, is returned to the earth, in the form of bird's excreta.

 The basis of Agrobacterium-mediated genetic engineering is that the T-DNA of A. tumefaciens is excised and integrates into the plant genome as part of the natural infection process by this bacterium. So, any foreign DNA inserted into the T-DNA will also be integrated.

In 'peritrichous' bacteria flagella are present all over the body surface. e.g., Salmonella, E.coli, Clostridium.

The residents of deep-sea hydrothermal vents obtain energy from inorganic chemicals surrounding them. Bacteria, for example, extract energy from the chemical bonds of hydrogen sulphide (H₂S) and then add the freed hydrogens to carbon dioxide to synthesize organic nutrient compounds. Organisms like these, which use inorganic chemicals to manufacture nutrient molecules, are called chemoautotrophs.

Methanogen is used in the production of biogas.

Rhizobium is a bacteria which acts as a biofertilizer in association with leguminous plant.

Yes, it is the correct.

Nitrobacter is genus of mostly rod-shaped, gram-negative, and chemoautotrophic bacteria. Nitrobacter plays an important role,  in nitrogen cycle by oxidizing nitrite,  into nitrate in soil.

Bacterias are capable of decomposing biodegradable substances only. Since polythene bags are non-biodegradable substances, it cannot be decomposed by bacteria.