Fensom and spanner electroosmotic flow hypothesis, Biology

Assignment Help:

Fensom and Spanner Electroosmotic Flow Hypothesis

In electroosmosis the ions flow across a membrane in response to electrical gradient. Ions pull along water and other contents because of solvent drag. In this hypothesis it is visualised that sap flows in the lumen of sieve element and electroosmosis occurs across the sieve plate. The basic idea of this model is represented in Figure. The pores of sieve are negatively charged and many positive ions are associated with them. The companion cells of consecutive sieve elements are shown to be engaged in K+ uptake and release. This generates a (K+) gradient in the direction of phloem sap flux; the fluxes of other solutes are coupled to K+ flux and move along with the electroosmotic flow from one sieve tube to the next.

1433_Fensom and Spanner Electroosmotic Flow Hypothesis.png

Figure: Active uptake of K+ by the companion cell from its associated sieve tube on the left and secretion of K+ into the sieve tube at the right side by its companion cell generate both e potential difference and a K+ concentration gradient. This causes a now of K+ ions and other solutes from right hand side to left.


Related Discussions:- Fensom and spanner electroosmotic flow hypothesis

Chordata, what are the two main subdivisions of the phylum chordata

what are the two main subdivisions of the phylum chordata

Explain radiology, Radiology is a medical specialty that employs the use of...

Radiology is a medical specialty that employs the use of imaging to both diagnose and treat disease visualised within the human body. Radiologists use an array of imaging technolog

State the principles of behaviour change communication, Principles of behav...

Principles of behaviour change communication - BCC should be integrated with program goals from the starting. BCC is a necessary part of diabetes prevention, care and support p

Functions of cell wall, FUNCTIONS OF CELL WALL 1.       Provides shape ...

FUNCTIONS OF CELL WALL 1.       Provides shape to plant cell rigidity to cells. 2.       Functions as a barrier to entry of pathogens into the cells. 3.       Provides pr

Contact guidance - modes of cell movement, Contact guidance - Modes of Cell...

Contact guidance - Modes of Cell Movement Besides chemical / ionic factors that regulate cell movement in developing embryos, physical factors as well appear to play a role in

Elimination of the risk factors - diabetes mellitus, Q. Elimination of the ...

Q. Elimination of the risk factors - diabetes mellitus? In other words, in diabetes it refers to maintaining of normal body weight, healthy nutritional practice, regular physic

Explain expansion in plasma volume during pregnancy, Normal 0 f...

Normal 0 false false false EN-IN X-NONE X-NONE

Initiation of development - development biology, Initiation of Development ...

Initiation of Development - Development Biology We know that the various events collectively called the activation programme. These events are directly related to the formatio

Determine the improper occlusal scheme, Improper Occlusal Scheme This i...

Improper Occlusal Scheme This is an important cause of failure as the implant are more sensitive to occlusal trauma and leads to prosthetic failure and bone loss. The susceptib

Successive changes in animal life during hydrosere, Successive Changes in A...

Successive Changes in Animal Life during Hydrosere The successive changes in plant communities in the different seral communities of a hydrosere. The question arises, is ther

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd