Definition

Noun: A solution that has the same osmotic pressure as another specified solution, typically blood. It is a solution in which the concentration of solutes is equal to that inside a cell or a reference fluid, resulting in no net movement of water across a semipermeable membrane.

Usage

This term is used primarily in scientific contexts, especially in biology, chemistry, and medicine, to describe solutions used in experiments or medical procedures to maintain cell volume and function.

Examples

• The red blood cells were placed in an isosmotic solution to prevent them from shrinking or swelling.
• For this experiment, we need to prepare an isosmotic solution with the same osmotic pressure as the cell culture medium.
• Intravenous fluids are often isosmotic solutions relative to blood plasma.

Advanced Usage

• The term is often used comparatively, as in "isosmotic with" a specific reference.
  • The saline solution was made isosmotic with mammalian blood.
• In physiology, an isosmotic solution for one type of cell or tissue may not be isotonic (have the same effect on cell volume) if the solutes can permeate the cell membrane.

Variants and Related Words

• Isotonic solution (n): In many biological contexts, this is used interchangeably with "isosmotic solution," though there is a technical distinction. An isotonic solution is specifically one that does not cause a change in cell volume.
• Hyperosmotic solution (n): A solution with a higher osmotic pressure.
• Hypoosmotic solution (n): A solution with a lower osmotic pressure.
• Isosmotic (adj): Describing the property of having equal osmotic pressure.
  • The two fluids were isosmotic.

Synonyms

• Isotonic solution (in common biological usage)
• Iso-osmotic solution

Antonyms

• Hyperosmotic solution
• Hypoosmotic solution
• Hypertonic solution
• Hypotonic solution

Noun

1. a solution having the same osmotic pressure as blood