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The cell was first discovered by Robert Hooke in 1665 using a microscope. The first cell theory is credited to the work of Theodor Schwann and Matthias Jakob Schleiden in the 1830s. In this theory the internal contents of cells were called protoplasm and described as a jelly-like substance, sometimes called living jelly.
Since the invention of the microscope in the seventeenth century it has been known that plant and animal tissue is composed of cells : the cell was discovered by Robert Hooke. The plant cell wall was easily visible even with these early microscopes but no similar barrier was visible on animal cells, though it stood to reason that one must exist.
Hooke most famously describes a fly's eye and a plant cell (where he coined that term because plant cells, which are walled, reminded him of the cells in a honeycomb [2]). Known for its spectacular copperplate of the miniature world, particularly its fold-out plates of insects, the text itself reinforces the tremendous power of the new microscope.
Eukaryotic cells contain organelles including mitochondria, which provide energy for cell functions; chloroplasts, which create sugars by photosynthesis, in plants; and ribosomes, which synthesise proteins. Cells were discovered by Robert Hooke in 1665, who named them after their resemblance to cells inhabited by Christian monks in a monastery.
(A pair of letters exchanged between Hooke and Newton (9 December 1679 and 13 December 1679, omitted from Waller's The Posthumous Works of Robert Hooke, M.D. S.R.S.) Henderson, Felicity (22 May 2007). "Unpublished Material from the Memorandum Book of Robert Hooke, Guildhall Library MS 1758". Notes and Records of the Royal Society of London.
Robert Hooke's discovery of cells in 1665 led to the proposal of the cell theory. Initially it was believed that all cells contained a hard cell wall since only plant cells could be observed at the time. [9] Microscopists focused on the cell wall for well over 150 years until advances in microscopy were made.
1858 – Rudolf Virchow proposed that cells can only arise from pre-existing cells; "Omnis cellula e celulla," all cell from cells. The Cell Theory states that all organisms are composed of cells (Schleiden and Schwann), and cells can only come from other cells (Virchow). 1864 – Louis Pasteur disproved the spontaneous generation of cellular life.
Outline of cell biology. Cell structure: Cell coined by Robert Hooke; Techniques: cell culture – flow cytometry – microscope – light microscope – electron microscopy – SEM – TEM – live cell imaging; Organelles: Cytoplasm – Vacuole – Peroxisome – Plastid. Cell nucleus. Nucleoplasm – Nucleolus – Chromatin – Chromosome ...