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

Collection of blood, Collection of Blood It is a procedure done rout...

Collection of Blood It is a procedure done routinely for diagnosis. It can be done in various ways. 1) Capillary Sampling  The heel is the most useful area i

The nurse''s role in relieving the child''s stress, The Nurse's Role  in ...

The Nurse's Role  in Relieving  the Child's Stres s Turning passive experiences into active ones that facilitate the child's healthy - Problems-I  adjustment to hospitalization

Determine the importance of calcium in soils, Determine the importance of C...

Determine the importance of Calcium in soils Calcium in soils is usually abundant except in acid soils, which occur in humid areas due to excessive leaching. Deficiency of calc

How much of solution to add 10ng of dna in a reaction, I dissolve 4µg of DN...

I dissolve 4µg of DNA in 1mL of water. How much of this solution would I need in order to add 10ng of DNA in a reaction?

Which pga as the first co2 fixation product, PGA as the first CO2 fixation ...

PGA as the first CO2 fixation product was discovered in photosynthesis of: 1. Bryophyte 2. Gymnosperm 3. Angiosperm 4. Alga Alga

What is atrial switches operations, What is Atrial Switches Operations (Sen...

What is Atrial Switches Operations (Senning or Mustard Operation) ? In transposition of the great arteries there is ventriculo arterial discordance whereby aorta arises from ri

Explain the urinary excretion of ascorbic acid, Explain the Urinary excreti...

Explain the Urinary excretion of Ascorbic Acid? The urinary excretion of ascorbic acid falls when the dietary intake is low. Since the tissues are not saturated, a greater part

Agriculture, what''s a mature female sheep called

what''s a mature female sheep called

Describe metabolic syndrome, Describe Metabolic Syndrome ? As discussed...

Describe Metabolic Syndrome ? As discussed, the risk factors like obesity, high blood pressure, high blood glucose or impaired glucose tolerance, and dyslipidaeinia are very im

Theory of embryology - pre-formation theory, PR E FORMATION THEORY - ...

PR E FORMATION THEORY - Proposed by Marcello Malpighi. Studied chick egg and proposed his work in "De ova-incubato". According this different part of embryo previousl

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