 Hey everybody Dr. O here. In this video we're going to talk about the fluid compartments. So all the water in your body can basically broken up into intracellular fluid and extracellular fluid. Now a little fraction of it's going to be other, but we don't have to worry about that. So intracellular fluid is the fluid inside your cells. And as you'll see in just a moment, more than half about 60% of your body water is inside your cells. That's intracellular fluid. Extracellular fluid is all the fluid that's outside of your cells and surrounds your cells. And that can be broken down into two compartments. Interstitial fluid is the fluid between your cells and plasma is the water, the fluid portion of your blood. So again, intracellular fluid, all the fluid that's inside your cells. Extracellular fluid, all the fluid outside your cells. And that can be broken down into interstitial fluid, the fluid between your cells and plasma, the fluid in your blood. Okay, just one more thing here. Just real big picture. I covered this a lot more in osmosis way back in our first unit together. But intracellular fluid, the primary cation or positive ion inside your cells is going to be potassium. So potassium is what helps potassium and protein help hold water inside your cells. And then the primary cation or positive ion outside your cells is going to be sodium. So you have this interplay where potassium and protein are pulling water in your cells. Sodium is pulling it out. This is why I think we have so many issues where people are developing hypertension, too much blood plasma, too much blood volume leading to blood high blood pressure, or edema, too much fluid accumulating between our cells. Because if we eat a diet that's high in sodium and low in potassium, you can see how some of this, some of this would occur. All right, we'll cover that in more detail in actually the next video. Here we see this total body water use intracellular fluid is about 60% like we mentioned. And then the other 40% is going to be the extracellular fluids, plus that little sliver of other there. This means though that, you know, the average sized male has seven gallons, about 25 liters of fluid inside their cells. That's pretty amazing. You think about it. And then we've already mentioned that it's potassium and protein that holds that water inside your cells. And then sodium plays a big role in pulling water out of your cells. This is just showing why it's so important. Like how much water you have is great, but where it is is just as important. If you have to see here in the middle, if you have too little water in your cells, they become shriveled up or cremated and they start to lose their function because proteins will denature. Which means a cell without proteins is a cell without enzymes. It can have a metabolism. So you're going to see the cell membrane would take damage too. So this cells is going, it's going to die if you don't get this, this imbalance fixed quickly. And then the far right, if there's too much fluid in your cells, that'll cause them to swell and they could potentially even burst. One condition that might be related here is if someone sweats a whole bunch and they're losing all sorts of electrolytes, primarily sodium, and all they do is replace it with water. Or if someone drinks way too much fluid like this, the cases where you've heard of where people can drink so much water, they die. It's actually causing hyponatremic encephalopathy. All that fluid is swelling the cells of the brain and that's actually what can be fatal. So yes, even water can kill you. So this is why it's so important to know where your water is. And that's how we talk about electrolytes so much because they help coax water to move to different areas in your body. Alright, then lastly here, just going back to those two examples of extracellular fluid, basically about 20% of extracellular fluid is going to be plasma, that little red sliver there, the fluid portion of your blood, very, very important. Then the other 80% will be your interstitial fluid, the fluid between your cells. And I've covered this in earlier units, but your body produces or forces fluid out of your capillaries to create interstitial fluid. It reabsorbs most of it. What doesn't get reabsorbed becomes lymphatic fluid. So that's another example. There are other extracellular fluids. Lymph or lymphatic fluid would be one all of your your cirrus membranes like your pericardial cavity, peritoneal cavity, and your plural cavity, they would all have some extracellular fluid there. The aqueous humor of your eye would be fluids. We don't care so much about those because generally they're going to stay pretty stable. But there are types of extracellular fluid that aren't that don't fall into one of these two categories just so you know. Okay, that's your fluid compartments. I hope this helps. Have a wonderful day. Be blessed.