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SLIME SUBSTANCE AND STRANDS IN SIEVE ELEMENTS
Author(s) -
Evert R. F.,
Derr W. F.
Publication year - 1964
Publication title -
american journal of botany
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.218
H-Index - 151
eISSN - 1537-2197
pISSN - 0002-9122
DOI - 10.1002/j.1537-2197.1964.tb06713.x
Subject(s) - phloem , sieve tube element , sieve (category theory) , biology , molecular sieve , traverse , biophysics , botany , geology , biochemistry , mathematics , combinatorics , geodesy , catalysis
Studies of the secondary phloem of 6 species of woody dicotyledons revealed that slime is not normally dispersed throughout the vacuole of mature sieve elements, but occurs in the form of discrete strands that traverse the cell and run from cell to cell through the sieve‐plate pores. As many as 5 fine strands, each measuring less than 0.5μ in diameter, were observed in a single pore. Less than 30% of pore area was occupied by strands. Thus, the pores are mostly open, and intervacuolar continuity exists between cells. These structural characteristics of pores offer strong support for the concept of mass flow.