Navigation Links
Osmosis is not driven by water dilution
Date:4/4/2013

Osmosis the flow of a solvent across a semipermeable membrane from a region of lower to higher solute concentration is a well-developed concept in physics and biophysics. The problem is that, even though the concept is important to plant and human physiology, osmosis is understood in biology and chemistry in a much simpler and often incorrect way.

"A range of surprising misconceptions about osmosis continue to appear in papers, web sites and textbooks," says Eric Kramer, professor of physics at Bard College at Simon's Rock in Great Barrington, Mass. "Wrong ideas about osmosis are especially common in educational materials aimed at students of chemistry and biology. Once learned, these errors influence the thinking of professionals throughout their careers."

The thermodynamic theory of osmosis was published by J.W. Gibbs in 1897, and during the next half-century dozens of other scientists published explanations for it in terms of interactions between the solute and solvent molecules. "Many of the greatest scientists of the 20th century took a turn at it," says Kramer, "A textbook in 1951 offered the first coherent telling of the whole theory."

Though physicists have had this complete and correct explanation since the 50s, chemistry and biology never caught up. Why? One reason is because the incorrect theory is much easier. "The thermodynamic explanation can be pretty dense, and features entropy, which can be scary for people," he says. "The correct theory would be harder to teach at an introductory level, although I'm working with a textbook author who plans to spread the word."

Reach back into your memory for your first science lesson on osmosis. It probably involved a demonstration with a bag of sugar with holes poked in it. When dunked into water, the water rushed into the bag. Using this example of osmosis, Kramer lays out the common misconceptions:

(1) "The first misconception is that osmosis is l
'/>"/>

Contact: Eric Kramer
ekramer@simons-rock.edu
413-528-7476
Dick Jones Communications
Source:Eurekalert

Page: 1 2

Related biology news :

1. Global Surgical Devices Market Growth Driven by Improving Standards of Living and Longer Life Expectancies, Research Shows
2. Global warming has driven Europes mountain plants to migrate 2.7 meters upwards in 7 years
3. Medical device, health professionals attend first national conference on value-driven engineering
4. The academic jungle: Ecosystem model reveals why women are driven out of science
5. Fluctuating environment may have driven human evolution
6. Saber-toothed cats in California were not driven to extinction by lack of food
7. Photovoltaics beat biofuels at converting suns energy to miles driven
8. Ozone treated water v. lethal microbial material
9. Unexpected crustacean diversity discovered in northern freshwater ecosystems
10. New methods for better purification of wastewater
11. Costs for changing pollution criteria in Florida waters likely to exceed EPA estimates
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:8/12/2015)... , Aug. 12, 2015  Synaptics Inc. (NASDAQ: ... interface solutions, today announced that four of its ... solution, have officially been named FIDO Certified™ by ... of the certification, Synaptics, Natural ID™ fingerprint solutions ... Authentication Framework (UAF) standard and are interoperable among ...
(Date:8/6/2015)... Germany , August 6, 2015 /PRNewswire/ ... SensoMotoric Instruments (SMI) shows the world,s first ... based on Epson,s Moverio BT-200 see-through head mounted display ... new solution, unprecedented quality and efficiency is brought to ... displays. For the first time, professionals and researchers can ...
(Date:8/4/2015)... Aug. 04, 2015 ... has announced the addition of the ... and Service), Sub-Segment (Computer Forensics, Network Forensics, ... Types, Service, Vertical and Region - Global ... offering. By Component (Hardware, Software, ...
Breaking Biology News(10 mins):Synaptics Announces FIDO Certification of Natural ID Fingerprint Solutions 2Synaptics Announces FIDO Certification of Natural ID Fingerprint Solutions 3SMI Shows First Eye Tracking Upgrade for Augmented Reality Glasses 2SMI Shows First Eye Tracking Upgrade for Augmented Reality Glasses 3Digital Forensics Market - The Market Represents a Compound Annual Growth Rate (CAGR) of 11.3% From 2015 to 2020 2
... a novel study, a University of Oklahoma researcher and collaborators ... test the toxicity of water or sediment was resistant to ... is the first to demonstrate that the indicator species may ... entirely unreliable source of information about ecosystem health. ...
... and forest disturbances may have a silver lining for ... a 10-year study that monitored 112 bears in Alberta,s ... and his colleagues found that warmer temperatures and easier ... grizzlies to build more body fat, known to increase ...
... scanners that give scientists a direct line of sight ... Fraser University researchers will use to help Ballard Power ... of these fuel cells in vehicles can substantially reduce ... Nano X-ray Computed Tomography (NXCT) tools will become part ...
Cached Biology News:OU research team finds a common bioindicator resistant to insecticides 2Climate change has silver lining for grizzlies 2Scientists to gain from view inside of fuel cells 2
(Date:8/27/2015)... - BIOREM Inc. (TSXV: BRM) ("Biorem" or "the Company") today announced ... 2015. Biorem,s complete second quarter financial statements and MD&A have been ... except earnings per shareThree-months ended , Six -months endedJune 30 , ... , 2014 Revenue , 4,709 , ... , 1,656 , 56 , 3,188 ...
(Date:8/27/2015)... , August 27, 2015 GlassesOff (OTCBB: ... processing functions in the human vision system, announced today a ... point guard Chris Paul to develop a new ... want to improve their real-life on-court performance. Vision ... whether it is shooting a ball or blocking a pass. ...
(Date:8/27/2015)... ... August 27, 2015 , ... METTLER ... expertly narrows down the product choices to a manageable shortlist of bench and ... list to models that fit best with the customer’s industry and application. ...
(Date:8/27/2015)... (PRWEB) , ... August 27, 2015 , ... ... Personalized Medicine, recently presented new data on the relationship of genetics and hypertension ... World Congress on Heart Disease in Vancouver, British Columbia, Canada. The event, which ...
Breaking Biology Technology:BIOREM Reports $718,000 Net Earnings for the Second Quarter 2BIOREM Reports $718,000 Net Earnings for the Second Quarter 3Eight-Time All-Star Chris Paul and GlassesOff Partner to Develop Innovative Mobile App Designed to Improve On-Court Performance 2Eight-Time All-Star Chris Paul and GlassesOff Partner to Develop Innovative Mobile App Designed to Improve On-Court Performance 3METTLER TOLEDO Updates Online Scale Selection Tool 2Proove Biosciences Presents Ground-Breaking Data on Genetics and Heart Disease at 20th World Congress on Heart Disease 2Proove Biosciences Presents Ground-Breaking Data on Genetics and Heart Disease at 20th World Congress on Heart Disease 3
... Rapid Production, Increased Bioavailability, MOUNTAIN VIEW, Calif., ... are either incurable or difficult to treat allures ... prized, due to their,therapeutic potential, stem cell therapies ... Stem cell research progresses at a fast pace; ...
... Inc. (Nasdaq: CEPH ) and Eurand NV ... Paragraph IV Certification Notice Letter on October 20, ... to the U.S.,Food and Drug Administration (FDA) by ... a generic version of the 15 mg and,30 ...
... 71% of Evaluable Patients in the Trial,s First Stage ... Achieved Objective Tumor Responses- ... Second Stage-, TUSTIN, Calif., Oct. 21 Peregrine,Pharmaceuticals, Inc. (Nasdaq: ... cancer and serious viral,infections, today announced that updated preliminary data from ...
Cached Biology Technology:Innovation and Strong Therapeutic Potential Seen in Adult Stem Cells, According to Frost & Sullivan 2Innovation and Strong Therapeutic Potential Seen in Adult Stem Cells, According to Frost & Sullivan 3Cephalon and Eurand Announce Notification of Generic Filing for Cyclobenzaprine Hydrochloride Extended-Release Capsules 2Cephalon and Eurand Announce Notification of Generic Filing for Cyclobenzaprine Hydrochloride Extended-Release Capsules 3Cephalon and Eurand Announce Notification of Generic Filing for Cyclobenzaprine Hydrochloride Extended-Release Capsules 4Peregrine Pharmaceuticals Reports Progress in Its Phase II Trial of Bavituximab Plus Docetaxel in Patients With Advanced Breast Cancer 2Peregrine Pharmaceuticals Reports Progress in Its Phase II Trial of Bavituximab Plus Docetaxel in Patients With Advanced Breast Cancer 3Peregrine Pharmaceuticals Reports Progress in Its Phase II Trial of Bavituximab Plus Docetaxel in Patients With Advanced Breast Cancer 4
... dye terminators, template DNA, primers, salts or ... products have proved critical for both standard ... to work with dye terminator cycle sequencing ... The unique uniformity of the magnetic paeticles ...
Mature rat whole blood (Sprague-Dawley, averaging 7-8 weeks of age, either sex) is collected at the time of slaughter and processed within 45 minutes. It is then filtered through gauze, pooled in an ...
X-gal,1g...
RayBio Human Atherosclerosis Antibody Array 1.1 (4) with Accessory, detects 40 inflammatory factors (for lysate) Class: Antibody Array Products Product Group: Antibody Array...
Biology Products: