question_answer

  What is cell theory and who proposed this theory?  What modification Virchow made in this theory?

Answer:

  Cell theory was presented by two biologists, Schleiden and Schwann. According to this                 (i) cell is the basic unit of structure.                 (ii) cell is the basic unit of function.                                                                                                                                          (2)                 Rudolf Virchow further modified the cell theory by stating that all cells arise from pre-existing cells.         (1)