Thank you so much... *S

Nice of you to reply.

Regards,

Stan-

wrote in message
. ..
In article ,
Stan Dornfeld wrote:

As a machinist and with some metal experience, I find it interesting how
the
tendril actually bends toward the curl.
A bimetalic strip, as used in a thermostat, will bend on temperature
change
because on one side of the strip that metal will expand or contract faster
than that of the other.

I'm curious how it's effected in the plant.

When a plant bends toward the light, or away from the ground, one side
of the growing stem elongates its cells more than the rest, so it's a
little like the bimetallic strip. In twining plants, there would have
to be a diagonal or helical component to this. You may have noticed
that when a clinging structure like a twining stem or the tendrils on
peas or squash contacts something suitable it stops extending and waving
around and grabs hold, something that happens over a period of
hours or less. I don't know the mechanism of detecting the contact
and responding to it, but I think it's pretty cool. No doubt some work
has been done on it.

Btw, I think you've been describing a twining stem, a main structure of
the plant that bears leaves and flowers and wraps itself up the support.
Tendrils are specialized structures derived from leaves that grab hold
of something and hang on. Peas, grapes, squash, melons, cucumbers, etc
all have tendrils, while pole beans and morning glories twine.

I hope somebody who actually knows something about this will correct
my errors and give you a better reply. I mostly answered because nobody
else did., and it's a good question that deserves an answer. ;-)