They break open directly in the blood, in our blood circulation as a result of being damaged by some other type of factor. So, for example, when our red blood cells age and when they become very fragile, if they are squeezed through that very tight capillary, they can actually lyse. And by lysing, they release the components to the blood plasma of our cardiovascular system. So about 10% of the red blood cells lyse and this process is known as hemolysis directly in our blood circulation. Their remnants are eventually picked up by the macrophages, as we'll see in just a moment. Now, the majority of the aged or damaged red blood cells end up in our spleen, in our liver, or in our lymph nodes.