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

Floating plants, what are floating plants? detailed information

what are floating plants? detailed information

Define some essential facts about the fats, Define some Essential facts abo...

Define some Essential facts about the Fats? 1) Fats are essential in diets to facilitate satiety, high-energy intakes, and absorption of fat-soluble vitamins and provide essent

What could have caused the discrepancy, If the class's value did not match ...

If the class's value did not match the expected value of water, let's assume everyone was actually correctly using the devices and there was no "user error." What could have caused

Why the pancreas is considered a mixed gland, Q. What is a mixed gland? Why...

Q. What is a mixed gland? Why the pancreas is considered a mixed gland? Mixed gland is a gland that produces exocrine and endocrine secretions. The pancreas is an example of

What are the in-vivo imaging techniques, What are the in-vivo imaging techn...

What are the in-vivo imaging techniques The first of the in-vivo imaging techniques, computer tomography (CT) scanning, came on stream in the early 1970s. As technologies devel

Define oven - nutritional biochemistry, Define Oven - Nutritional Biochemis...

Define Oven - Nutritional Biochemistry? Oven is a general term used to describe a chamber or enclosed compartment for heating, baking, or roasting food, as in a stove, or for f

Define bioavailability of pyridoxine, Define Bioavailability of pyridoxine?...

Define Bioavailability of pyridoxine? A recent review by Gregory confirms that bioavailability of vitamin B 6 in a mixed  diet is about 7570, with approximately 8% of this tot

Illustrate about the intra-ocular pressure, Illustrate about the Intra-ocul...

Illustrate about the Intra-ocular pressure It is the pressure maintained inside the eye above the atmospheric pressure. It is higher than fluid pressure in any other tissue (2-

Excretory organs in different animals, EXCRETOR Y ORGANS In protozo...

EXCRETOR Y ORGANS In protozoa through plasmalemma by diffusion. Contractile vacuole present for osmoregulation (absent in parasitic and marine protozoa). In porifera and

Restructured meat products, Re s t r u c t u re d Meat Products ...

Re s t r u c t u re d Meat Products Restructuring technique is used for developing convenience products with texture in between intact steak and a comminuted product.

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