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

The Endocrine system, What are the two models that explain Mechanism of Hor...

What are the two models that explain Mechanism of Hormone Action on their target?

Surgical treatment of infective endocarditis, Cardiac surgical intervention...

Cardiac surgical intervention has an increasingly important role in the treatment of intracardiac complications of endocarditis. Retrospective data suggest that mortality is unacce

Locomotion, Locomotion All animals, simple or complex, are able of per...

Locomotion All animals, simple or complex, are able of performing necessary bodily functions. One of these functions is Locomotion. Motility is one of the characteristics and

Why does thymine replace uracil in dna, Q. Why does thymine replace uracil ...

Q. Why does thymine replace uracil in DNA? The difference between DNA and RNA is existence of a hydroxyl (-OH) group on 2' carbon of the ribose sugar in the backbone. Removal o

Guidelines for diagnosis and treatment planning, Guidelines for diagnosis a...

Guidelines for diagnosis and treatment planning The diagnosis and planning the case is by far the most important step in the entire sequence of the treatment and due considerat

Organisation of nervous system, Organisation of Nervous System Nervou...

Organisation of Nervous System Nervous systems are composed of nerve cells or neurons and glial cells. In the latter half of the 19 th century it was strongly believed that

Define the term underweight, Define the term Underweight? Just as overw...

Define the term Underweight? Just as overweight is the result of a positive energy balance irrespective of the etiology, underweight results when the energy balance is negative

Define the wealth care delivery, Define the Wealth Care Delivery ? The ...

Define the Wealth Care Delivery ? The challenge that exists today in many countries is to reach the whole population with adequate health case services and to ensure their util

Explain Genetic equilibrium for genes with two alleles, What is the mathema...

What is the mathematical expression of the genetic equilibrium for genes with two alleles? Is this statistical distribution the same as the statistical distribution of the respecti

Determine the nutritional and functional role of bromine, Minerals : Bromin...

Minerals : Bromine                 Food Source       Brominated flour  Nutritional Functional role Not known to be essential to humans. Dough improver: KBrO 3 impr

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