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# can someone explain this to me?
I vaugely remember my biology GCSE and osmosis was something about water being absorbed into cells. I also remember stuff about the cell wall breaking down if there was too much water - but beyond that I'm lost.
(I helped save b3ta! rob, Fri 18 Jun 2004, 23:41, archived)
# It's to do with concentration gradients.
Water moves across the membrane from an area of low concentration (of sugar or whatever) to an area of high concentration, in an attempt to equalise.

Quite why it does this I can't remember...
(I helped save b3ta! supermoore: HUNG, Fri 18 Jun 2004, 23:42, archived)
# Pfft, it's not like it THINKS about it or anything,
it just does. Entropy in action.
(goat thinks you're shit, Fri 18 Jun 2004, 23:46, archived)
# Osmosis
is the transfer of water from a high water concentration to a low water concentration across a semi-permeable membrane.

Like in cells and that.
(I helped save b3ta! Mystery_Bob, Fri 18 Jun 2004, 23:43, archived)
# er...
but is there a joke?
(I helped save b3ta! rob, Fri 18 Jun 2004, 23:44, archived)
# The joke
is that the solute particles shouldn't go from left to right. However, This will occur
if a pressure greater than the osmotic pressure of the right-hand solution on the membrane were applied to the solution on the left.
(I helped save b3ta! DogHorse plop, Fri 18 Jun 2004, 23:44, archived)
# thats meant to be the joke
but clearly the joker doesnt have a comprehensive knowledge of biology.
(I helped save b3ta! siredsmithjr, Fri 18 Jun 2004, 23:45, archived)
# *slaps thigh*
*forwards to everyone*
(I helped save b3ta! rob, Fri 18 Jun 2004, 23:46, archived)
# It's the way I tell 'em
(I helped save b3ta! DogHorse plop, Fri 18 Jun 2004, 23:46, archived)
# Forwarding thighs now,
are we?
(I helped save b3ta! Chrico is a bounder and a cad, Fri 18 Jun 2004, 23:47, archived)
# In the picture it's occuring in the wrong direction,
hence anarchy.
(I helped save b3ta! supermoore: HUNG, Fri 18 Jun 2004, 23:45, archived)
# I think
in this crazy world of no physics, the water is actually moving across to the higher water concentration.
(I helped save b3ta! Mystery_Bob, Fri 18 Jun 2004, 23:45, archived)
# So...
If the left side has no salt and the right side has loads of salt, then the higher concentration of water is always on the right side, because the salt reduces its concentration.
(I helped save b3ta! siredsmithjr, Fri 18 Jun 2004, 23:45, archived)
# Basically
the tendancy is for the concentration to attempt to balance across a semi permeable membrane. Water flows from the side with the lowest concentration of solute (dissolved stuff) to the side with the highest, thus diluting it. Bringing the psi values (water potential) closer together.
Water potential can be considered as the ratio of water to solute.
(Xybex, Fri 18 Jun 2004, 23:46, archived)