Answer :
An isotonic solution has the same concentration of water as the cell placed in the solution.
What is tonicity?
Tonicity is a measure of the effective osmotic pressure gradient; the water potential of two solutions separated by a partially permeable cell membrane.
Tonicity depends on the relative concentration of selective membrane impermeable solutes across a cell membrane which determine the direction and extent of osmotic flux.
There are three classifications of tonicity that one solution can have relative to another:
1. Hypertonic solution: A hypertonic solution has a greater concentration of non-permeating solutes than another solution.
In biology, the tonicity of a solution usually refers to its solute concentration relative to that of another solution on the opposite side of a cell membrane; a solution outside of a cell is called hypertonic if it has a greater concentration of solutes than the cytosol inside the cell.
When a cell is immersed in a hypertonic solution, osmotic pressure tends to force water to flow out of the cell in order to balance the concentrations of the solutes on either side of the cell membrane.
2. Hypotonic solution: A hypotonic solution has a lower concentration of solutes than another solution.
In biology, a solution outside of a cell is called hypotonic if it has a lower concentration of solutes relative to the cytosol.
Due to osmotic pressure, water diffuses into the cell, and the cell often appears turgid, or bloated.
3. Isotonic solution: A solution is isotonic when its effective osmole concentration is the same as that of another solution.
In biology, the solutions on either side of a cell membrane are isotonic if the concentration of solutes outside the cell is equal to the concentration of solutes inside the cell.
In this case the cell neither swells nor shrinks because there is no concentration gradient to induce the diffusion of large amounts of water across the cell membrane.
Water molecules freely diffuse through the plasma membrane in both directions, and as the rate of water diffusion is the same in each direction, the cell will neither gain nor lose water.
To learn more about isotonic solution: https://brainly.com/question/15111297
#SPJ4
