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As a result, the concentration of sucrose increases in the sieve tube elements. This causes water to move into the sieve tube element by osmosis, creating pressure that pushes the sap down the tube. In sugar sinks, cells actively transport sucrose out of the sieve tube elements, first to the apoplast and then to the symplast of the sink.
Sieve tube members are shorter and wider with greater area for nutrient transport while sieve cells tend to be longer and narrower with smaller area for nutrient transport. Although the function of both of these kinds of sieve elements is the same, sieve cells are found in gymnosperms, non-flowering vascular plants, while sieve tube members are ...
With sufficient contact time, such water will permeate the membrane bag into the draw solution, leaving the undesirable feed constituents behind. The diluted draw solution may then be ingested directly. Typically, the draw solutes are sugars such as glucose or fructose, which provide the additional benefit of nutrition to the user of the FO device.
A molecular sieve is a material with pores (voids or holes), having uniform size comparable to that of individual molecules, linking the interior of the solid to its exterior. These materials embody the molecular sieve effect , the preferential sieving of molecules larger than the pores.
As such, mass flow is a subject of study in both fluid dynamics and biology. Examples of mass flow include blood circulation and transport of water in vascular plant tissues. Mass flow is not to be confused with diffusion which depends on concentration gradients within a medium rather than pressure gradients of the medium itself.
The water vascular system of the sea star consists of a series of seawater-filled ducts that function in locomotion and feeding and respiration. Its main parts are the madreporite, the stone canal, the ring canal, the radial canals, the lateral canals, and the tube feet. The sieve-like madreporite allows entry of seawater into the stone canal ...
When the water pressure within the xylem reaches extreme levels due to low water input from the roots (if, for example, the soil is dry), then the gases come out of solution and form a bubble – an embolism forms, which will spread quickly to other adjacent cells, unless bordered pits are present (these have a plug-like structure called a ...
Proteins are separated by the charge in agarose because the pores of the gel are too large to sieve proteins. Gel electrophoresis can also be used for the separation of nanoparticles. Gel electrophoresis uses a gel as an anticonvective medium or sieving medium during electrophoresis.