Schleiden and schwann biography of rory
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Eclipses
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The chimericeukaryote: origin of the nucleus from the karyomastigont in amitochondriate protists
NASA Technical Reports Server (NTRS)
Margulis, L.; Dolan, M. F.; Guerrero, R.
2000-01-01
We present a testable model for the origin of the nucleus, the membrane-bounded organelle that defines eukaryotes. A chimeric fängelse evolved via symbiogenesis by syntrophic merger between an archaebacterium and a eubacterium. The archaebacterium, a thermoacidophil resembling extant Thermoplasma, generated hydrogen sulfide to protect the eubacterium, a heterotrophic swimmer comparable to Spirochaeta or Hollandina that oxidized sulfide to sulfur. urval pressure for speed swimming and oxygen avoidance led to an ancient analogue of the extant cosmopolitan bacterial consortium "Thiodendron latens." By eubacterial-archaebacterial genetic integration, the chimera, an amitochondriate heterotroph, evolved. This "earliest branching protist" that formed by permanent DNA recombination generated the nucleu
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Cell theory
Biology of cells
In biology, cell theory is a scientific theory first formulated in the mid-nineteenth century, that living organisms are made up of cells, that they are the basic structural/organizational unit of all organisms, and that all cells come from pre-existing cells. Cells are the basic unit of structure in all living organisms and also the basic unit of reproduction.
Cell theory has traditionally been accepted as the governing theory of all life,[1] but some biologists consider non-cellular entities such as viruses living organisms[2] and thus disagree with the universal application of cell theory to all forms of life.
History
With continual improvements made to microscopes over time, magnification technology became advanced enough to discover cells. This discovery is largely attributed to Robert Hooke, and began the scientific study of cells, known as cell biology. When observing a piece of cork under the scope, he was able