 There you go, Dr. O. In this video I want to cover the three types of capillaries. So you can see here we have continuous capillaries, fenestrated capillaries, and sinusoid. So the key difference is what size of things they'll allow through. So continuous capillary, it's the most common type of capillary. Most of the capillaries in your body are going to be continuous capillaries. So like the name implies, they're continuous. There's no large openings, there's no holes. So very small things are able to transport through continuous capillaries. Most of your continuous capillaries also have transport vesicles that will carry things in and out. So continuous. So capillaries are designed to move things, oxygen, carbon dioxide, nutrients, and waste. So continuous capillaries will move lots of materials, but only things that are small. Your blood-brain barrier is a special kind of continuous capillary that doesn't have these transport vesicles, so it moves very little stuff. We'll cover that with the nervous system, but the blood-brain barrier is designed to basically isolate your brain and spinal cord from the rest of your body. All right, so those are continuous capillaries. They move small things. Next we have the fenestrated capillaries, and just so you know, fenestrum means windows. So these are going to move maybe medium-sized things because they have these openings called fenestrations or windows. So they're still pretty tight, and they don't have large gaps like the sinusoids do, but they can move a lot more material and things that are slightly larger. So where might you see these? The small intestine, because that's where especially the genuina of the small intestine is where like 80 to 90% of digestion absorption takes place. Your kidneys would have fenestrated capillaries. Think about the gallons and gallons of material that they have to filter through every day. The hypothalamus and the pituitary gland, those would be good examples as well of areas that have fenestrated capillaries. So if you need to move a whole lot of stuff or things that are slightly larger, you would want a fenestrated capillary. The third kind is called a sinusoid. These literally have gaps and spaces in them, so they're going to move large things. Things that could never fit through a continuous capillary or a fenestrated capillary. So this would be kind of looks porous like Swiss cheese, right? But this would be even some cells can fit through these large plasma protein cells. These kind of things are going to have to fit through these special sinusoids. Where might you find these? The liver. The liver has to move unbelievable amounts of things, and the things that it are making like plasma proteins have to squeeze out a bone marrow, right? The bone marrow is making cells. They have to be able to fit through these openings to get into your circulatory systems. Lymph nodes are going to have sinusoids, but those are going to be carrying lymph, not blood. So you're going to see these sinusoids in other places too, but those are going to be the key areas. One last thing about sinusoids though, these openings are so large and that's great that lots of good things can get through, but also means potentially that bad things can get through. So it's key to remember that sinusoids are going to be lined with macrophages. Macrophages are immune cells that are cell eaters, right? They will engulf things that shouldn't be there. They also will warn your immune system if things are showing up that shouldn't be there. So because these large openings were kind of vulnerable, so that's why your sinusoids are lined with macrophages. So all right, I hope this helps. Have a wonderful day. Be blessed.