At 7:06 PM 8/14/96 -0700, k.gould at auckland.ac.nz wrote:
>Is procambium functional in water transport? If not, I wonder at what
>stage in differentiation it becomes so?
Kevin--
Procambium cells are alive and have end walls.
My guess is that they transport only in the
sense of standard osmosis (xylem initials) and/or
facilitated or active transport (phloem initials).
Until the cytoplasm disintegrates along with the
end wall openings I'd bet that the evaporative-
pull style of transport is non-functional. It
sounds like something worth investigating...I'd
bet that the phloem initials are functional well
in advance of visible differentiation but that
xylem initials lag behind. That is certainly
the case in the root meristem.
ross
______________________________________________________________
|
Ross Koning | Koning at ecsu.ctstateu.edu
Biology Department | http://koning.ecsu.ctstateu.edu/
Eastern CT State University | Phone: 860-465-5327
Willimantic, CT 06226 USA | Fax: 860-465-5213
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Plant Physiology is Phun!
/\|___/\ //\______COOH NH-CH2-CH=C-CH2OH \/OH
| | | | | | || //\___ \CH3 /\|/\\/\\COOH
\/ \/|\/| \\/ \ / N || N | |
/\ | |__|= NH | || || //\//\
| COOH \\ /\ / O
COOH H2C=CH2 N NH
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