isotonic solution

[rosieburk]

when a cell is in an isotonic solution is there any movement of any molecules across the membrane at this point?

[canalon]

What do you think? Think about the properties of the membranes and about the laws of diffusion.

[rosieburk]

i know there is no net movement of water molecules into or out of the cell. But do any other molecule move across the membrane?

Also does that mean the cell mass remains the same?

[vaibhavsmarty]

well that depends in what reference you are talking about.That means whether solution is isotonic with respect to glucose,sodium,or any other macromolecule which may influence the osmotic properties of the cell.
If all the factors are kept "isotonic" then the net movement of any molecule will be zero.And hence there is no physical or metabolic change in the cell.

[qiamond]

actually dynamic equilibrium exists. the concentration of the components will be kept. but may some common physical change happens? such as the evaporation of the water from the surface

[tianlai]

Think about a RBC in blood. Blood is the isotonic solution to RBC, but many substances are still changed through the membrane. So the key feature depends on the cell that is dead or living. If the cell is dead, only water passes through the membrane.

[MrMistery]

either way, there is still movement across the membrane. And from the original question i guess it is safe to assume we are discussing a living cell