Talk:Tonicity

Defintion Comment

I thought tonicity referred to the solution with reference to the cell. i.e. 7% sodium chloride solution would be a hypertonic solution with respect to almost all living cells. 81.179.75.219 07:50, 3 July 2006 (UTC)

Tonicity is a unitless comparison of the solute concentration of one solution to another. Although it is often used to describe the solute concentration of extacellular fluid relative to the intracellular fluid, it need not be used this way. Tonicity can be expressed between any solutions separated by a semi-permeable membrane. I hope that this clears things up for you Slevit1 (talk) 20:10, 20 February 2008 (UTC)

I am really confused about this page. I feel it is really off the reality according to what I read elsewhere at http://www.biotech.ufl.edu/EM/data/osmos.html Could an expert verify? --The PA 02:56, 7 September 2006 (UTC)

What, exactly, do you think is contradictory? Slevit1 (talk) 20:10, 20 February 2008 (UTC)

i dont think this page should be merged with osmoles

Change semipermeable membrane to partially permeable membrane — Preceding unsigned comment added by 94.101.161.175 (talk) 12:10, 6 March 2014 (UTC)

Merge proposal

I'm proposing to merge isotonic, hypotonic, and hypertonic into this article. I think having several sections for these terms in here would be sufficient. - tameeria (talk) 20:16, 9 December 2007 (UTC)

Addendum: Per Wikipedia:Naming conventions, article names should be preferably nouns and adjectives should be redirects to nouns. In this case, "tonicity" is the noun that fits all of these adjective titles. - tameeria (talk) 04:44, 11 December 2007 (UTC)

• The merge makes sense to me--the content of each is essentially redundant and could be better served as a single topic with several redirects. I'll help w/ the merge if it goes forward... — Scientizzle 22:06, 11 December 2007 (UTC)

I'd agree with merging. One really can't understand any of the concepts without reference to the other two. The background material is going to be the same for all three. And when there get to be more refs, most of them will be relevant to all three.

As for the name, gee, if a gin'n'tonic is a noun, then wouldn't an isotonic be one too?  :-)

David.Throop (talk) 23:17, 11 December 2007 (UTC)

*lol* Maybe there should be a page for isotonic (beverage)? :-) Actually, there is one for isotonic (exercise physiology) since the term is used for muscles, too. And then there's isotone and isotonic regression as well, so there probably needs to be some sort of disambiguation. - tameeria (talk) 02:16, 12 December 2007 (UTC)

I agree with the merging also. Forluvoft (talk) 17:02, 12 December 2007 (UTC)

Merging, good idea. Tim Vickers (talk) 17:14, 12 December 2007 (UTC)

I'll get about merging them, then. Master of Puppets _{Call me MoP!☺} 00:36, 17 January 2008 (UTC)

How should this be incorporated?

I want to add information, but I'm not quite sure as to how to make it fit with the rest of the article. Basically, this entire article refers to tonicity between a cell and its external environment. However, tonicity does not have to relate to a cell. For example, a hypertonic solution is simply one with a greater impermeable solute concentration than the solution to which it is being compared. You can separate any two fluids with a semi-permeable membrane and have one be hyper/hypo/isotonic to the other. This is often used in reference to a cell, but does not need to be. Any ideas on how to incorporate this? Slevit1 (talk) 15:29, 21 February 2008 (UTC)

no comment —Preceding unsigned comment added by 212.72.11.30 (talk) 06:58, 17 May 2008 (UTC)

I think that the problem with this article would be solved very simply by indicating that in biology (where the term is most commonly used) the difference "tonicity" and "osmolarity" is mainly due to the urea, bicarbonate and glucose contents of the solutions on either side of the plasma- (or cell-) membrane. Urea, glucose and bicarbonate readily passes through any biological membrane that is permeable to water (urea and bicarbonate pass through the aquaporins, or "water channels" in cell membranes; glucose passes freely through GLUT transporters). Thus, a biologically isotonic solution (e.g. "isotonic saline") is hyposmotic (osmolality = 287 mosmol/kg H20) with respect to blood plasma (301 mosmol/kg H20) or the interior of red blood cells, because both these solutions (blood plasma and red cell cytoplasm) contain urea, glucose and bicarbonate which pass freely through the cell membrane. Another point of interest is that sharks' blood plasma is "isotonic" with mammalian red blood cells, but its osmolality is equal to that of sea water, nearly 4 times higher than that the osmolality of mammalian plasma. The discrepamcy is made up by very high plasma levels of urea in sharks' blood. I do not know how the boney fish cope with their hyperosmolar surroundings, other than what is suggested in this article, i.e. that they "drink" large amounts of sea water to make up for the losses through their gills, and then excrete the salt. Jkoeslag 28 December 2008.

Isotonic

Why on earth 2 separate sections, one headed "Isotonic Solution" and the other "Isotonicity"?? Cgingold (talk) 21:13, 13 March 2009 (UTC)

Also is there a reason why the definitions of hypertonic and hypotonic seem to be opposing the visual guides? — Preceding unsigned comment added by 69.126.27.228 (talk) 01:59, 25 November 2012 (UTC)

Tonicity and intermuscular injections.

The article reads

In some cases of suspensions intended for intramuscular injection, a slightly hypotonic solution is preferred in order to increase the dissolution and absorption of the drug by absorbing water from the surrounding tissues.

Did the author mean to say hypertonic? Or hypotonic because the water solution absorbs into the tissue? -Arm (talk) 22:45, 10 May 2011 (UTC)

This article is hard to understand

I think this article mixes up solutions and cells to the point where it isn't understandable for a casual reader. I think it needs a rewrite. — Preceding unsigned comment added by Yer maw (talk • contribs) 15:00, 27 November 2012 (UTC)

Hypertonicity (physiological, as in the opposite of hypotonicity) redirects to this article

This is obviously incorrect and quite misleading. 95.204.194.187 (talk) 13:46, 8 September 2017 (UTC)