. Elementary plant physiology. Plant physiology. Growth* n second section was taken, the walls of some of the elements have become thickened, and the protoplasts have undergone dissolution. The presence of the dead cells makes impossible any~elongation, excepf that permitted by the elastic stretching of tfieir firm walls. After the power of elongation is lost, growth Fig. 4.—Diagram of longitu- dinal section of a stem, tnp^ apical meristem ; tnep^ epider- mal meristem ; wzwz, medullary meristem ; mv^ vascular meri- stem ; jepy epidermis; ec^ cor- tex ; ic^ cortical parenchyma; endy endodermis
. Elementary plant physiology. Plant physiology. Growth* n second section was taken, the walls of some of the elements have become thickened, and the protoplasts have undergone dissolution. The presence of the dead cells makes impossible any~elongation, excepf that permitted by the elastic stretching of tfieir firm walls. After the power of elongation is lost, growth Fig. 4.—Diagram of longitu- dinal section of a stem, tnp^ apical meristem ; tnep^ epider- mal meristem ; wzwz, medullary meristem ; mv^ vascular meri- stem ; jepy epidermis; ec^ cor- tex ; ic^ cortical parenchyma; endy endodermis ; ccy central cylinder; /, pericycle ; /, phloem ; b^ xylem ; ^;«, peri- medullary zone; w, medulla. After Bonnier and Leclerc du Sablon. \.^}. in thickness may continue indefinitely by the action of cells in the phloem, especially of the geneiative layer, or cambium. The cylinder of fibrovascular tissue and its sheath with thS enclosed pith constitute a morphological unit known as a, stele; the ar- rangement of the stelar components varies in different species. Cut sections from older parts of a woody stem in which elon- gation has wholly ceased. Note the increased development of. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original MacDougal, Daniel Trembly, 1865-1958. New York, London [etc. ] Longmans, Green, and Co.
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectplantph, bookyear1902
