How do Trees Really lift Water to their Leaves?

BC:
Who cares?
If it were not for fusion all you would get was squashed gas.

Saying the sun is driven by gravity is like saying my central heating runs on a match.
OK, without a match to light the pilot light, the heating wouldn't work.
But it's still gas that heats my house.

It's still time for you to learn some physics and maths.
Why did you post that rubbish?
Why don't you listen?

Titre du document / Document title
Osmosis and solute-solvent drag : Fluid transport and fluid exchange in animals and plants
Auteur(s) / Author(s)
HAMMEL H. T. ; SCHLEGEL Whitney M. ;
Résumé / Abstract
In 1903, George Hulett explained how solute alters water in an aqueous solution to lower the vapor pressure of its water. Hulett also explained how the same altered water causes osmosis and osmotic pressure when the solution is separated from liquid water by a membrane permeable to the water only. Hulett recognized that the solute molecules diffuse toward all boundaries of the solution containing the solute. Solute diffusion is stopped at all boundaries, at an open-unopposed surface of the solution, at a semipermeable membrane, at a container wall, or at the boundary of a solid or gaseous inclusion surrounded by solution but not dissolved in it. At each boundary of the solution, the solute molecules are reflected, they change momentum, and the change of momentum of all reflected molecules is a pressure, a solute pressure (i.e., a force on a unit area of reflecting boundary). When a boundary of the solution is open and unopposed, the solute pressure alters the internal tension in the force bonding the water in its liquid phase, namely, the hydrogen bond. All altered properties of the water in the solution are explained by the altered internal tension of the water in the solution. We acclaim Hulett's explanation of osmosis, osmotic pressure, and lowering of the vapor pressure of water in an aqueous solution. His explanation is self-evident. It is the necessary, sufficient, and inescapable explanation of all altered properties of the water in the solution relative to the same property of pure liquid water at the same externally applied pressure and the same temperature. We extend Hulett's explanation of osmosis to include the osmotic effects of solute diffusing through solvent and dragging on the solvent through which it diffuses. Therein lies the explanations of (1) the extravasation from and return of interstitial fluid to capillaries, (2) the return of luminal fluid in the proximal and distal convoluted tubules of a kidney nephron to their peritubular capillaries, (3) the return of interstitial fluid to the vasa recta, (4) return of aqueous humor to the episcleral veins, and (5) flow of phloem from source to sink in higher plants and many more examples of fluid transport and fluid exchange in animal and plant physiology. When a membrane is permeable to water only and when it separates differing aqueous solutions, the flow of water is from the solution with the lower osmotic pressure to the solution with the higher osmotic pressure. On the contrary, when no diffusion barrier separates differing parts of an aqueous solution, fluid may flow from the part with the higher osmotic pressure to the part with the lower osmotic pressure because the solute molecules diffuse toward their lower concentration and they drag on the water through which they diffuse. This latter osmotic effect (diffusing solute dragging on solvent or counterosmosis) between differing parts of a solution has long been neglected and ignored when explaining fluid fluxes in plant and animal physiology. For two solutions separated by a semipermeable membrane, osmosis is the flow of its solvent from the solution with the lower solute concentration into the solution with the higher solute concentration. For two contiguous solutions not separated by a semipermeable membrane, counterosmosis is the flow of solution with the higher solute concentration toward the solution with the lower solute concentration.
Revue / Journal Title
Cell biochemistry and biophysics ISSN 1085-9195 CODEN CBBIFV

Experiment showing solvent drag and solute density applied tension to water filled vertically suspended silicone tubing.

Tritalion:
Hello.

I have wondered what raises the water in plants. This video:

explains that driving force is transpiration, a process in which water diffuses from stomata into the atmosphere.

What exactly pulls the molecules of water into the air?

age5:
I was sitting on my porch watching the trees sway in a gentle wind and thought to myself "how do those trees get so much water up to their leaves. Then it came to me as I thought that a tree isn't a static object like a rock. It is constantly moving as it sways to and fro. I thought to my school days and the venous return theory based on one way valves in the veins which squirt the blood up to the heart through movement of muscles, not pure pressure. So it dawned on me, why can't trees use the same technique? I love my porch.

@Agefive,
The swaying of branches and the movement of leaves could well play an important roll in the movement of sap. I have applied the density flow to the vascular and arterial systems and used it to great effect with Inclined Bed Therapy. Thanks for your comment.

Alachus:
Surely if gravitation is not a primary component of plant growth and implicitly of sap dynamics, then growing plants aboard the ISS would be easy, or - rather - even easier than on Mother Earth. However this obviously incompetent dude says it was more complicated than it seemed back home: spaceflight.nasa.gov/station/crew/exp6/spacechronicles13.html

Interesting footage from BBC Frozen planet showing density flow in the Antarctic ocean.

Well worth viewing.

Valachus

Thank you for the link and for your comment.

Siphon in a vacuum proves atmospheric pressure irrelevant to siphon effect.

Radio Interview with Patrick Timpone on One Radio Network

20 years ago Andrew made a phenomenal discovery in circulation and how gravity acts upon fluid density changes that take place in all fluids where water is evaporated. In trees (Where this theory began) evaporation from the leaves alters the density of sap. In the body, the warm lungs and airways provide the same density changes in the blood and other fluids. It was not long before it became obvious that posture was incredibly more important than anyone could imagine. To make use of these density changes and allow them to assist the circulation all we needed to do was to manage our posture.
This was a Eureka moment of such magnitude it went off the scale for Andrew and instantly gave birth to Inclined Bed Therapy.
Show Highlights:
-Andrew explains how learning about how trees uptake water led him to understand the benefits of inclined bed therapy