Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Holocrine Secretion and Kino Flow in Angiosperms: Their Role and
  Physiological Advantages in Plant Defence Mechanisms   Kinos are plant exudates, rich in polyphenols, produced by several
angiosperms in reaction to damage. They flow out of kino veins,
schizolysigenous ducts composing an anatomically distinct continuous system of
tangentially anastomosing lacunae produced by the vascular cambium, which
encircle the plant. Kino is secreted holocrinously into the vein lumen by a
cambiform epithelium lined by suberized cells that separate kino veins from the
surrounding axial parenchyma. A model describing kino flow in eucalypts is
presented to investigate how vein distribution and structure, as well as kino
holocrine loading, crystallization, and viscosity affect flow. Considering
viscosity, vein anatomy, and a time-dependent holocrine loading of kino, the
unsteady Stokes equation was applied. Qualitatively, kino flow is similar to
resin flow. There is an increase in flow towards the vein open end, and both
pressure and flow depend on vein dimensions, kino properties and holocrine
loading. However, kino veins present a much smaller specific resistance to flow
compared to resin ducts. Also, unlike resin loading in conifers, holocrine kino
loading is not pressure-driven. The pressure and pressure gradient required to
drive an equally fast flow are smaller than what is observed on the resin ducts
of conifers. These results agree with previous observations on some angiosperms
and suggest that holocrinous gum flow may have lower metabolic energy costs;
thus presenting physiological advantages and possibly constituting an
evolutionary step of angiosperms in using internal secretory systems in plant
defence mechanisms compared to resin flow in conifers. Understanding of how
these physiological and morphological parameters affect kino flow might be
useful for selecting species and developing more sustainable and economically
viable methods of tapping gum and gum resin in angiosperms.

29
The categories of this paper are: funct-an
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The categories of this paper are: alg-geom
25
The categories of this paper are: patt-sol
6
The categories of this paper are: astro-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: adap-org
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The categories of this paper are: dg-ga
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The categories of this paper are: bayes-an
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The categories of this paper are: eess
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The categories of this paper are: nucl-ex
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The categories of this paper are: chem-ph
5
The categories of this paper are: gr-qc
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The categories of this paper are: supr-con
4
The categories of this paper are: cond-mat
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The categories of this paper are: ao-sci
1
The categories of this paper are: cs