Growth and Permeability of Century-Old Cells

  title={Growth and Permeability of Century-Old Cells},
  author={Daniel Trembly Macdougal},
  journal={The American Naturalist},
  pages={393 - 415}
  • D. Macdougal
  • Published 1 September 1926
  • Biology
  • The American Naturalist
(1) Cells of the medulla of Carnegiea gigantea may continue to grow for nearly a century and to be active until the death of the tree. (2) Parenchymatous cells of the medulla retain their meristematic condition during the longer period mentioned. (3) Great numbers of parenchymatous cells of all ages are transformed into vascular bundles forming strands connecting with the woody cylinder. (4) The estimated rate of enlargement of medullary cells is greater in the second than in the first half… 

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