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Origin and Evolution of Life — BIOLOGY STD 12 Science — Question

Maharashtra BoardEnglish MediumSTD 12 ScienceBIOLOGYOrigin and Evolution of Life5 Marks
Question
Explain the process of formation of eobionts.
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Answer

  1. Protobionts or coacervates were colloidal aggregations of hydrophobic proteins and lipids (lipoid bubbles).
  2. They grew in size by taking up material from surrounding aqueous medium.
  3. During their growth they became thermodynamically unstable and split into smaller units. These were called microspheres.
  4. They were proteinoids formed from colloidal hydrophilic complexes surrounded by water molecules.
  5. These bodies were like primitive cells having outer double-membrane. Across this membrane diffusion and osmosis may have occurred. They were more stable than coacervates.
  6. Coacervates and microspheres were non-living colloidal aggregations of lipids and proteinoids respectively.
  7. But they showed growth and division like living cells.
  8. These colloidal aggregations turned into first primitive living system called eobionts or protocell.

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