Dense granule

Dense granules (also known as dense bodies or delta granules) are specialized secretory organelles. Dense granules are found only in platelets and are smaller than alpha granules. The origin of these dense granules is still unknown, however, it is thought that may come from the mechanism involving the endocytotic pathway. Dense granules are a sub group of lysosome-related organelles (LRO). There are about three to eight of these in a normal human platelet.