What is the difference between hypertonic and hypotonic solutions?
When a cell is immersed into a hypertonic solution, the tendency is for water to flow out of the cell in order to balance the concentration of the solutes. Likewise, the cytosol of the cell is conversely categorized as hypotonic, opposite of the outer solution. Hypotonic refers to a lesser concentration.
That IV is full of saline, a liquid with the same concentration of solutes as your blood cells. Because you want your blood cells to sit in an isotonic solution. An isotonic solution is when two solutions, separated by a semipermeable membrane, have equal concentrations of solutes and water.
- A hypotonic solution is one in which the concentration of solutes is greater inside the cell than outside of it, and a hypertonic solution is one where the concentration of solutes is greater outside the cell than inside it.
- This more concentrated outside solution is termed hypertonic. The less concentrated outside solution is termed hypotonic. Since distilled water has far less solute concentration than cell fluid, it is termed hypotonic.
- Pure water is definitely hypotonic. A saturated salt solution is definitely hypertonic. In between, depending on the cell and the salt, there will be an isotonic concentration, where everything is balanced.
Blood is isotonic. Hypertonic solutions have less water ( and more solute such as salt or sugar ) than a cell. Tapwater and pure water are hypotonic. A single animal cell ( like a red blood cell) placed in a hypotonic solution will fill up with water and then burst.
- This diffusion of water across a semi-permeable membrane is called osmosis. Similarly, if there is a higher concentration of dissolved salt outside of the cell (a hypertonic environment), then H20 will diffuse "out" from the cell and the cell will dehydrate and shrink and cellular metabolism will cease.
- The plant wilts because there is a loss of turgor pressure. What happens when a plant cell is placed in a hypotonic solution? The greatest concentration of water is outside the cell. Therefore, water enters the cell and fills the central vacuole, causing the contents of the plant cell to press against the cell wall.
- An isotonic solution refers to two solutions having the same osmotic pressure across a semipermeable membrane. This state allows for the free movement of water across the membrane without changing the concentration of solutes on either side. AP Chemistry: Help and Review / Science Courses.
IV fluid tonicity
|0.9% NaCl (normal saline)||isotonic|
|Lactated Ringer's solution||isotonic|
|D5W (acts as a hypotonic solution in body)||isotonic|
- 5% Dextrose in Water is a special case, though. Although it is technically isotonic, it acts upon the body as if it is hypotonic. The reason is because once the dextrose has been absorbed, there is only plain water left. Obviously, plain water without anything in it is hypotonic!
- A hypotonic solution is any solution that has a lower osmotic pressure than another solution. In the biological fields, this generally refers to a solution that has less solute and more water than another solution.
- D5W is technically isotonic, but it becomes hypotonic once in the body so it pulls fluid out of the vasculature and into the cells. This is because once D5W is in the body, the dextrose is metabolized and you are left with free water, which is hypotonic.
Updated: 3rd October 2019