Differentiate isotonic, hypertonic and hypotonic solutions.

Isotonic, hypertonic, and hypotonic are terms used to describe the concentration of solutes in a solution compared to another solution. Here's how they differ:

1. Isotonic Solution: An isotonic solution is one in which the concentration of solutes is the same both inside and outside the cell. If a cell is placed in an isotonic solution, there will be no net movement of water into or out of the cell. This means the cell will neither shrink nor swell. This is because the amount of water the cell gains by osmosis is the same as the amount it loses, so the volume of the cell remains constant. An example of an isotonic solution is normal saline solution, used in medical treatments.

2. Hypertonic Solution: A hypertonic solution is one in which the concentration of solutes is greater outside the cell than inside it. If a cell is placed in a hypertonic solution, water will move out of the cell to the area of higher solute concentration. This causes the cell to shrink, a process known as crenation. An example of a hypertonic solution is sea water.

3. Hypotonic Solution: A hypotonic solution is one in which the concentration of solutes is lower outside the cell than inside it. If a cell is placed in a hypotonic solution, water will move into the cell where the solute concentration is higher. This causes the cell to swell and can lead to the cell bursting, a process known as lysis. An example of a hypotonic solution is pure water.

In summary, the difference between isotonic, hypertonic, and hypotonic solutions lies in the relative concentration of solutes in the solution compared to inside the cell, which affects the movement of water into or out of the cell.