A&P 1: Please help me understand "hypertonic" & "hypotonic"!!

stpauligirl · Sep 21, 2005

For the life of me I can't keep these 2 straight. I'll think I've got it down and then along comes a question about whether something is "hyper/hypotonic to" something else...Aaaagghhhh!
What is wrong with me? It doesn't seem like it should be so difficult to understand.
Thanks for any help you can offer!

hypertonic means more stuff in it.

Hypertonic means less stuff in it.

I am afraid if I say more it might just become confusing.....I am struggling with the same exact thing....as a matter of fact I posted a few days ago about a question I had

If a red bllod cell is in distilled water is the cell hyper- hypo- or isotonic to the distilled water.....gave me big headache but I think I got it right and determined that the red blood cell must be hypertonic to the distilled water because the cell has more stuff in it .

Good luck. :)

stpauligirl · Sep 21, 2005

hypertonic means more stuff in it.
Hypertonic means less stuff in it.
I am afraid if I say more it might just become confusing.....I am struggling with the same exact thing....as a matter of fact I posted a few days ago about a question I had
If a red bllod cell is in distilled water is the cell hyper- hypo- or isotonic to the distilled water.....gave me big headache but I think I got it right and determined that the red blood cell must be hypertonic to the distilled water because the cell has more stuff in it .
Good luck. :)

Correction, sorry about that

Hypertonic- more stuff

hypotonic-less stuff, it's late please forgive me :imbar

Marie_LPN, RN, LPN, RN · Sep 21, 2005

I'm assuming you can't remember which is hypertonic and which is hypotonic? As in you get their definitions mixed up?

Hypertonic means more than normal. The way i would remember this is hyperactive children. ("Whew, that kid is hyper, he is way too much for me!")

If i remembered that, then that's how i kept the two straight. For some reason, that worked for me.

stpauligirl · Sep 21, 2005

hypertonic means more stuff in it.
Hypertonic means less stuff in it.
I am afraid if I say more it might just become confusing.....I am struggling with the same exact thing....as a matter of fact I posted a few days ago about a question I had
If a red bllod cell is in distilled water is the cell hyper- hypo- or isotonic to the distilled water.....gave me big headache but I think I got it right and determined that the red blood cell must be hypertonic to the distilled water because the cell has more stuff in it .
Good luck. :)

BTW, god bless this message board :)

Achoo!, LPN · Sep 21, 2005

I'm assuming you can't remember which is hypertonic and which is hypotonic? As in you get their definitions mixed up?
Hypertonic means more than normal. The way i would remember this is hyperactive children. ("Whew, that kid is hyper, he is way too much for me!")
If i remembered that, then that's how i kept the two straight. For some reason, that worked for me.

Ditto to that!!

This will also come into play with other words- practice practice!! :)

hypertension - high blood pressure

hypotension- low blood pressure

Karen · Sep 21, 2005

Another good way to remember, especially when it comes to fluids is relating it to "concentration"

hyper = more concentrated (more stuff in the solution as compared to normal)

hypo = less concentrated (less stuff in the solution as compared to normal)

in the case of fluids they are compared to normal concentrations of body fluid. If they are more concentrated they are hyper, less concentrated they are hypo. Normal saline (0.9%) for example approximates the concentration of body fluids

Micci · Sep 21, 2005

Well it helps to understand what the prefixes hypo- and hyper- mean.

Hypo means below, lower than, under. The solution has less solute (disolved particles like salt) than the cell.

Hyper means above, excessive. The solution has more solute than the cell.

I'm sure you are well versed on concentration gradients, osmosis and diffusion- so I won't go into that.

If the solution is "hypo" below the solute concentration of the cell, the water in the cell leaves. Think of a water balloon losing water from many leaks- it shrivels up. If the solution is "hyper" above the solute concentration, the water rushes in- now think of a water balloon filling and filling until it bursts.

The water is attracted to the solute, so it will go where solute is high, either in or out.

If you are still having trouble, you can use the little trick my Biology professor taught us: Hypo; water's gotta go. Everyone giggled and groaned at that, but it kind of stuck with me.

student4ever · Sep 21, 2005

My teacher explained it this way. Hypertonic solution (hypertonic to the cell for example) means there is more added stuff in it, like previous posters explained. Because the hypertonic solution has more additives, it must have less WATER. If there is less water in the solution, the water wants to go toward the solution so there is equal water. And vice versa. She drew pictures of three fishies in fishbowls. One was normal sized, and one was big, the other little. The normal sized fish is in isotonic solution - water concentration is the same both inside the fish's cells and in the solution around it. The fishie that was big, was in a hypotonic solution (the solution is hypotonic to the fish's cells), meaning that because the solution has less additives, it has more water, so the water is going to go into the fish's cells and the fish will get big. There is an O in hypOtonic - OOOOOH my, the fish is BIG!!! The little fish is in a solution that is hypertonic to the fish's cells, meaning there is more additives, and less water. Therefore, the water will leave the fish's cells and go into the solution to find equillibrium. So, the fish got EETTY BEETTY (E in hypErtonic - eeety beety fishee!) Corny, I know, but it worked for me. Now, where it gets really confusing is when the question asks if the CELL is hyper- or hypo- tonic to the solution. In that case, the OOOH MY, BIG fishy is in a hypOtonic solution (less additive, more water so water moves towards cells). If the solution is hypOtonic to the fish's cells, then the cells must be hypErtonic to the solution, and the water goes towards the hypertonic solution. The EETY BEETY FISHEEE is in a hypErtonic solution, which means more additive in the solution, less water, so the water goes out of the fish's cells and into the solution around it. Therefore, the cells of the fish are hypOtonic to the solution, because less additive, more water, it wants to go where there is less water - the hypErtonic solution. Make sense? It makes a lot more sense with the diagrams she drew, but it's hard to draw those on a message board! Hope this helps you guys!

kayel · Sep 21, 2005

We covered this in class today also! What kind of diagram do you have to explain it? Love the idea of the fishie bowls!

Just to mention it, we will have monthly threads for A&PI so if we keep all the questions and answers in one thread, then everything is in one place (well, times number of months) ... here is the link for September:

https://allnurses.com/forums/showthread.php?t=119304

I'm enjoying Anatomy but it's a lot of work! Tomorrow I have my second lab in which we look at tissues and such. Woo hoo!

Hydakins · Feb 17, 2008

My teacher explained it this way. Hypertonic solution (hypertonic to the cell for example) means there is more added stuff in it, like previous posters explained. Because the hypertonic solution has more additives, it must have less WATER. If there is less water in the solution, the water wants to go toward the solution so there is equal water. And vice versa. She drew pictures of three fishies in fishbowls. One was normal sized, and one was big, the other little. The normal sized fish is in isotonic solution - water concentration is the same both inside the fish's cells and in the solution around it. The fishie that was big, was in a hypotonic solution (the solution is hypotonic to the fish's cells), meaning that because the solution has less additives, it has more water, so the water is going to go into the fish's cells and the fish will get big. There is an O in hypOtonic - OOOOOH my, the fish is BIG!!! The little fish is in a solution that is hypertonic to the fish's cells, meaning there is more additives, and less water. Therefore, the water will leave the fish's cells and go into the solution to find equillibrium. So, the fish got EETTY BEETTY (E in hypErtonic - eeety beety fishee!) Corny, I know, but it worked for me. Now, where it gets really confusing is when the question asks if the CELL is hyper- or hypo- tonic to the solution. In that case, the OOOH MY, BIG fishy is in a hypOtonic solution (less additive, more water so water moves towards cells). If the solution is hypOtonic to the fish's cells, then the cells must be hypErtonic to the solution, and the water goes towards the hypertonic solution. The EETY BEETY FISHEEE is in a hypErtonic solution, which means more additive in the solution, less water, so the water goes out of the fish's cells and into the solution around it. Therefore, the cells of the fish are hypOtonic to the solution, because less additive, more water, it wants to go where there is less water - the hypErtonic solution. Make sense? It makes a lot more sense with the diagrams she drew, but it's hard to draw those on a message board! Hope this helps you guys!

Exactly what I needed. I love this!

Lennonninja, MSN, APRN, NP · Feb 17, 2008

I had a rough time remembering this, and I listened to a podcast from a different university, and it really helped me. Check this one out, the way she explained it and did the few examples really cemented it in my brain - http://www.clickcaster.com/bio201