 Drastic. Everybody doctor, we're going to talk about the buffer systems. I don't make you know these in depth, but I think it's important that we introduce them. So first let's talk about acid-based balance. Here you see the pH scale, like temperature, like pressure, like everything else. Our body has to maintain a stable internal environment, the maintenance of homeostasis. And if we can't, we get sick. And if it can't too much over too long, we die. That's just reality, right? Life is balanced on this razor's edge of, if we go too far in either direction in many different scenarios, we can't survive that. So here you see the pH scale. It runs from zero to 14. This is covered in unit one, but pH of seven is neutral, pure water. Anything above a pH of seven would be a base, and then below a pH of seven would be an acid. So looking at body fluids on here, you see blood has a pH of 7.4. I usually say 7.35 to 7.45 urine and saliva puts the pH at 6.3 to 6.6. But those are variable. If you're in pH, you can change a whole bunch. We've covered that in the urinary system. What you wouldn't see somewhere down around two-ish, you might see your gastric juice, your stomach juice. So even your body can have fluids of different pHes, but most of them do hover in that six to seven range just so you know. So if your pH goes too high, like above 7.8, goes too low, definitely below seven, but even lower, not even quite that low, then that could be fatal. So we have to maintain this system. Now long-term, your body's pH is maintained by renal systems, renal compensation, and the respiratory system. So your kidneys and your lungs are primarily responsible for maintaining your pH by getting rid of excess acids in your body. But the buffers are going to be the temporary solutions, and they're super, super important because they can work quickly. So a buffer is just any chemical system, anything that resists change to pH. How buffers generally work is they'll behave like a weak acid if you put them in a basic environment. They'll behave like a weak base if you put them in an acidic environment just so you know. All right. So we talked about the main advantage of buffers is they work really, really quickly so they can maintain and stabilize pH. It takes minutes for your respiratory system to respond. It can take hours or days for your kidneys to compensate for major changes. So these are very, very important. All right. The three major buffer systems. So here's the hemoglobin, but you've got the carbonic acid bicarbonate buffer system. These are the important points. Most important buffer system in extracellular fluid. Then you have the phosphate buffer system. Most important, I would say, in intracellular fluid and urine. Then you have the protein buffer systems that are very important in work with both extracellular fluid and intracellular fluid. So here's the protein buffer system. If the pH starts to climb, if the pH goes too far above seven and becomes basic, the carboxyl group here can actually release a hydrogen ion and function like a weak acid to bring the pH back down. If the pH is dropping too low or you're becoming too acidic, you have the amino group there can actually accept additional hydrogen ions and function like a weak base, bringing the pH down. So this is why the protein buffer system, it can lower or raise the pH depending on the environment. The limiter here is this is primarily only free amino acids or amino acids that are on the end of peptide chains because the amino acids are held together by peptide bonds, then this won't work just so you know. So that's the protein buffer system. Hemoglobin is basically a special protein buffer. The hemoglobin and the blood pH from carbon dioxide are very important because this is where you have something that can be happening inside cells that has a major impact on the pH of extracellular fluids because the hemoglobin absorbs carbon dioxide, which when you're talking acid-base balance, whenever I say carbon dioxide, I think weak acid, carbonic acid. So it absorbs the carbonic acid to get rid of it. So that's actually so the hemoglobin buffer system plays a role in removing acids from from your extracellular fluids. We're very, very important there. All right. Just remember that hemoglobin is going to be buffering these hydrogen ions by by turning carbon dioxide carbonic acid into bicarbonate, which we'll cover later. All right. Then we have so here we do have more of this almost every cell in your body except for your red blood cells, some cancer cells. Most of the time, most of your cells are always generating carbon dioxide, which means your body's always always making acids. You've got to neutralize these acids. So most that look on the right hand side here, most the carbon dioxide is going to be converted to carbonic acid, which you can see can then dissociate into a hydrogen ion and bicarbonate. So which direction it's going is going to depend on the pH, but you see that your body can release acids or absorb or take up acids using this bicarbonate buffering system. So very, very important one. But the biggest thing to remember there is that when you see carbon dioxide, just just think carbonic acid. And that's why we have to we had when we're doing thought experiments as far as like with my respiratory to go up or down, do you want to get rid of more acids? Then you're going to breathe out faster. If you want to conserve acids, then you're going to want to breathe slower. We'll cover that when we actually talk about the acid based disturbances. Okay, but very, it is very important that you remember that there's way more acids being produced in your biotin basis. So you're way more likely to need to get rid of acids than to add more to the equation. This is just showing that we, so we actually have 20 times more bicarbonate in our bodies at any given moment than carbonic acid, which means that we can absorb and take on acid. So this buffering system works really well if your blood is becoming too acidic, it wouldn't help much the other direction. If your blood was becoming too basic. But thankfully, alkalosis conditions where your blood pH climbs too high are very, very rare. All right, this whole system in the end though is really controlled by that carbon dioxide we talked about earlier. If you've got too much acid in your blood, breathe out more carbon dioxide. Too little acid in your blood, breathe out less carbon dioxide. So we'll come back to all that. All right, then just lastly, the phosphate buffer system. Just remember, this is the most important one in intracellular fluid and your urine. As you see here, we have different with blood or phosphates are found in the body in different forms. One of them can behave like a weak base, one like a weak acid, and that's how it resists change to pH. So that one's not a very big deal. Okay, so that's a quick introduction to acid based balance. But most importantly, this is how your buffering systems provide that immediate solution to keep your pH from changing, giving your kidneys and lungs the time they need to actually deal with the problem. Hope this helps, have a wonderful day, be blessed.