Isotonic medium

Definition

An isotonic medium is a solution where the concentration of solutes outside the cell is equal to the concentration inside the cell. This balance prevents the net movement of water into or out of the cell, maintaining cellular stability.

5 Must Know Facts For Your Next Test

1. In an isotonic medium, cells maintain their normal shape and function because there is no net movement of water.
2. Isotonic conditions are crucial for bacterial cultures in laboratory settings to prevent cell lysis or shrinkage.
3. Prokaryotic cells, such as bacteria, thrive in isotonic environments because it stabilizes their internal environment.
4. The osmotic pressure in an isotonic medium is balanced with that inside the prokaryotic cells.
5. Common examples of isotonic solutions include saline (0.9% NaCl) and Ringer's lactate used in medical treatments.

Review Questions

Related terms

Hypertonic Medium: A solution where the concentration of solutes outside the cell is higher than inside, causing water to leave the cell.

Hypotonic Medium: A solution where the concentration of solutes outside the cell is lower than inside, causing water to enter the cell.

Osmosis:

The diffusion of water across a semipermeable membrane from a region of lower solute concentration to higher solute concentration.