nodule

Examples of nodule in the following topics:

• The Legume-Root Nodule Symbiosis

  • Many legumes have root nodules that provide a home for symbiotic nitrogen-fixing bacteria called rhizobia.
  • Rhizobia respond by releasing nodulation factor (sometimes just called nod factor), which stimulates nodule formation in plant roots.
  • Infection triggers rapid cell division in the root cells, forming a nodule of tissue.
  • Once the rhizobia have established themselves in the root nodule, the plant provides carbohydrates in the form of malate and succinate, and the rhizobia provide ammonia for the formation of amino acids.
  • Root nodules are formed when nitrogen fixing bacteria called rhizobia enter the cells of a host plant.

• Thyroid Gland Disorders

  • Many individuals may find the presence of thyroid nodules in the neck.
  • The majority of these thyroid nodules are benign (non-cancerous).
  • If the nodule is found to be non-cancerous, no other treatment is required.
  • If the nodule is suspicious, then surgery is recommended.
  • One may be able to feel a hard nodule in the neck.

• Early Discoveries in Nitrogen Fixation

  • He found that the nodules on the roots of legumes are the location where nitrogen fixation takes place.
  • Hellriegel did not determine what factors in the root nodules carried out nitrogen fixation.
  • Martinus Willem Beijerinck (March 16, 1851 – January 1, 1931), a Dutch microbiologist and botanist, explored the mechanism responsible, discovering that the root nodules contained microbes.
  • The bacteria in the root nodules are needed to provide nitrogen for legume growth, while the rhizobia are dependent on the root nodules as a environment to grow.and a source of nutrition.

• Anaerobiosis and N2 Fixation

  • In plants infected with Rhizobium, (legumes such as alfalfa or soybeans), the presence of oxygen in the root nodules would reduce the activity of the oxygen-sensitive nitrogenase.
  • Leghemoglobin buffers the concentration of free oxygen in the cytoplasm of infected plant cells to ensure the proper function of root nodules.
  • Leghemoglobin buffers the concentration of free oxygen in the cytoplasm of infected plant cells to ensure the proper function of root nodules.

• Symbiosis between Bacteria and Eukaryotes

  • Soil bacteria, collectively called rhizobia, are able to symbiotically interact with legumes to form nodules: specialized structures where nitrogen fixation occurs .
  • Nitrogenase, the enzyme that fixes nitrogen, is inactivated by oxygen, so the nodule provides an oxygen-free area for nitrogen fixation to take place.
  • Soybean (Glycine max) is a legume that interacts symbiotically with the soil bacterium Bradyrhizobium japonicum to form specialized structures on the roots called nodules where nitrogen fixation occurs.

• Nitrogen Fixation: Root and Bacteria Interactions

  • Soil bacteria, collectively called rhizobia, symbiotically interact with legume roots to form specialized structures called nodules in which nitrogen fixation takes place .
  • Soybean roots contain (a) nitrogen-fixing nodules.
  • Cells within the nodules are infected with Bradyrhyzobium japonicum, a rhizobia or "root-loving" bacterium.

• Endophytes and Plants

• Rheumatic Fever

• Nutrients from Other Sources

  • A symbiont is a plant in a symbiotic relationship with other organisms, such as mycorrhizae (with fungi) or nodule formation.
  • Root nodules occur on plant roots (primarily Fabaceae) that associate with symbiotic, nitrogen-fixing bacteria.
  • Within legume nodules, nitrogen gas from the atmosphere is converted into ammonia, which is then assimilated into amino acids (the building blocks of proteins), nucleotides (the building blocks of DNA and RNA, as well as the important energy molecule ATP), and other cellular constituents such as vitamins, flavones, and hormones.

• Hypersensitivity

  • Image shows diffuse ground glass pattern identified of typical centrilobular nodule in a patient with hypersensitivity pneumonitis, often caused by occupational exposure to dust.