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

Define advantages of direct microscopic count, Define Advantages of Direct ...

Define Advantages of Direct Microscopic Count? 1. It is easy, inexpensive and relatively quick method. 2. It gives information regarding size and morphology of microorganism

Determine the proecss of contrast sense, Contrast sense Sense of contr...

Contrast sense Sense of contrast is the ability to perceive slight changes in luminance between regions which are not separated by definite borders. This is as important as to

Explain pasteurization - method of food preservation, Explain Pasteurizatio...

Explain Pasteurization (temperature below 100° C) - method of food preservation? Pasteurization is a heat treatment that kills a part but not all the microorganisms present and

Respiration, comparitive chart on different types of respiration obserbed i...

comparitive chart on different types of respiration obserbed in different type of respiration organ of respiration , types of respiration,energy obtained , by product formed

Which are the plant tissues that form the plant roots, Which are the plant ...

Which are the plant tissues that form the plant roots? The roots have a central portion known as medulla made of vascular tissue (inner xylem and outer phloem). The medulla is

Draw a graph for an iv multiple infusion of a drug, Draw A graph for an IV ...

Draw A graph for an IV multiple infusion of a drug, and label on the graph where the trough (predose) blood draw would be collected and where the peak (postdose) blood draw would b

Determine the strengths of full battery measures, Determine the Strengths o...

Determine the Strengths of Full Battery Measures 1) Wide range of scores allow differential diagnosis in various cognitive disorders 2) More reliable, and sensitive 3) Br

Scanning electron microscopy, Scanning Electron Microscopy (SEM) While 'T...

Scanning Electron Microscopy (SEM) While 'TEM is useful to study the internal structul-c of thc ccll. SEM is an important technique if you wish to examine the surl'ace features o

Construct cdna samples, Once you have identified a few relevant mRNA specie...

Once you have identified a few relevant mRNA species, you wish to more closely examine their messages by sequencing. You do not have the time to search the genome and isolate the D

What is thigmotropism, What is thigmotropism? Thigmotropism is the move...

What is thigmotropism? Thigmotropism is the movement or growth of the plant in response to mechanical stimuli (touch or physical contact), as when a plant grows around a suppor

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