In addition, we have the thymus, the tonsils, and what are called Peyer's patches. Now, the thymus produces thymosin, which is a hormone we'll talk about that in the endocrine system a little bit, but it's really going to help, again, with this T-cell maturation. The tonsils help trap bacteria, and trap foreign bodies, and bacteria that we don't want from our throat. Then the Peyer's patches are going to do the same thing by destroying bacteria in our intestines. So we're really putting together this conjunction between these lymph nodes, these lymph organs, and then protection at this point. So what actually is the lymph? As I said before, it's this clear, watery fluid that's similar to blood plasma or similar to the fluid component of blood. We're recycling all of this plasma proteins and fluid back from the capillary beds that didn't make it back into circulation. So what the picture you're seeing is showing you is a diagram of the major lymph organs such as the spleen, and then the thymus up at the top. Then we can also see all of the lymph nodes, and a large portrayal of where the lymphatic system vesicles are. Now, the smaller picture on the right is showing you arterioles, which are the red tubes. This is where we have oxygenated blood flowing from the heart, and it's moving into the capillary bed, which are the smaller tubes to the right. Then they are, of course, being transferred to the venule, which is going to pick up all the deoxygenated blood and move it away from, or move it back to the heart to pick up oxygen from the lungs. Now, running through it, the green pictures are lymph nodes. This is where they're going to start to pick up the extra fluid that didn't make it back into the venules, right? So they're running just across it. Which means everything we did for the cardiovascular system is going to help promote this fluid pickup and this recycling of the lymph fluid. Now, this also means that movement of our skeletal muscles through yoga, holding postures and positions that we're not usually holding, this is all going to help with moving of this fluid along because we want it to make full cycles. So the big difference between lymph vessels, and lymph circulation, and cardiovascular circulation is that the lymphatic system is an open system. Meaning that we have fluid that's going to drain out into our tissues and be picked up by the lymph system, but it's not a closed system. So it's not only reaching the heart and the capillaries just like we had in circulatory system. Because of this, we have some similarities between the cardiovascular system. Like, it's moved along with skeletal muscle, the pulsing of the arteries can affect it, although when they don't actually pulse, the lymph vessels don't actually pump. We have smooth muscle as part of those lymphatic vessels, and then they have more valves, which means it prevents backflow just like veins. So what do we do is we want to have what's called lymph drainage, or we want to make sure that our nodes aren't stagnant. So we're turning over some of this lymphatic fluid by moving, by twisting, by doing all of these things that maybe a sedentary lifestyle that we're all stuck in isn't really promoting. So the picture that you're seeing is part of the module we're going to do today, where we start to move our bodies in a different way, doing some standing postures, and doing some sense salutations that will help to promote some of this movement. You can think that if you start to add this into your life daily or weekly basis, couple of minutes, or an hour a day, whatever is working for your lifestyle, we can start to see how this would help. By helping the stimulation of the lymph system and the lymph fluid, we're also helping our immune system because it's helping us to pick up foreign bacteria. It's helping us to turn over cells. If we need to stimulate T-cell or B-cell production, it's easier to do if we have a healthy lymph system.