Alright. So here we have an example problem that's asking, what is the tenacity of the outside solution in comparison to the inside of the cell? And we've got these 4 potential answer options down below. Now, of course, when we look at option d, it says electrotonic, which is not a word that we described in our last lesson video. So for sure, we know that we can eliminate answer option d.
But hypotonic, isotonic, and hypertonic are all terms that we talked about in our last lesson video, so it's going to be between one of these three answers. And so when we take a look at this image down below, what we need to notice is that there is a beaker, and the beaker has an outside solution, here, and then it has a cell, a red blood cell right here in the middle. And so this image is indicating that the outside solution is 10% solute and it indicates that inside of the red blood cell is 0.1% solute. And so what we need to realize is that 10% and 0.1%, when we compare these two numbers, 10% is higher. It is a higher solute concentration and 0.1% solute is lower.
And so recall from our last lesson video that isotonic is a word that means equal solute concentrations. But because 10% solute is higher than 0.1% solute, they are not equal to each other. 10% is not equal to 0.1%. So we know that we can eliminate answer option b, isotonic. It would be isotonic if they both had the exact same percentage of solute, the same concentration of solute.
And so what we need to realize here is that this problem is specifically asking us to label the tonicity of the outside solution. So we need to focus on the outside solution. The outside solution is 10% solute. It is higher solute concentration. And so recall the word that means higher solute concentration is hypertonic. Hypertonic means higher solute concentration, and so that means that the outside solution, the one that we're trying to label here, is going to be hypertonic with respect to the inside of the cell. So the correct answer here is going to be answer option c. And so this, of course, means that the inside of the red blood cell is going to be hypotonic. So inside here, we can say it is hypotonic, and the outside here, we can say is hypertonic. And so, again, we're labeling the outside solution, so it will be hypertonic and option a is not going to be correct for the outside solution.
So, option c, hypertonic, is the correct answer for this example, and I'll see you guys in our next video.