koning at ECSUC.CTSTATEU.EDU
Thu Mar 25 08:23:19 EST 1999
At 10:29 PM -0500 3/24/99, Delilah Stanley wrote:
>What is the difference in vascular and unvascular plants? Need to know,
>can't find the answer.
Vascular plants have vascular tissue (xylem and phloem)
for fluid transport of materials within the plant. The
non-vascular (preferred to unvascular) plants lack true
xylem and phloem.
Perhaps one of the most interesting cases in botany is
that of bryophytes. These plants lack true xylem and
phloem and therefore have been called non-vascular plants
for...well, for a long time. However, they DO have hydroids
and leptoids...cells that function in a vascular way...so
there is some controversy about whether they should be
called "vascular" or "non-vascular." The chief difference
between bryophytes and the truly vascular plants is lack
of lignin in bryophytes. Should one biosynthesis path...
and perhaps only one enzyme drive our concepts of vascularity?
This and other arguments are being advanced by a range of
biologists on both sides of the issue.
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: 860-465-4479
Electronic services composed and served from Macintosh hardware.
More information about the Plantbio