Question
Explain how xerarch succession progresses from serie to mesic condition and forms a stable climax community. You may use a flow chart.

Answer

Xerarch succession:

  1. In the primary xerarch succession, lichens are the pioneer species; they secrete acids to dissolve the rock, facilitating weathering and soil formation.
  2. With formation of soil, small plants like bryophytes occupy the area.
  3. They are succeeded by bigger plants over a long period of time. After several more seral stages, a stable climax forest community is formed.
  4. The climax community remains stable as long as the environment remains unchanged.
  5. The xeric habitat is changed into a mesic habitat.

 

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Stem cells hold the potential for manifold applications in biotechnology based next generation therapeutics. Scientists are trying to formulate better and more personalised treatment modalities against some seemingly irremediable diseases, by harnessing body's own stem cells and stem cell niche. Stem cells of different origin and level of potency are being investigated for tissue regeneration, treatment of bone defect, drug testing, gene therapy and cell based therapy for muscle damage, spinal cord injury, cancer therapy, etc. 'Tile properties of embryonic and adult stem cells to either self-renew or differentiate into multiple cell lineages make them an attractive source for cell therapies, tissue engineering and as model system for drug screening.

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