# Osteons
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**Osteons** are the cylindrical building blocks that make up [[bone#Compact & Spongy Bone|compact bone]], that go length ways down the bone and somewhat the concentric rings of a tree trunk. The **central canal** at the very center of the osteon is hollow and has [[blood vessels]] and [[nerves]] that run down the inside. These connect laterally through openings called **perforating canals**.
The "rings" of the osteon are called **lamellae**, and each one differentiates from the ones it is next to by a slightly different orientation of the [[collagen]] fibers. Along the lamellae you can see the **lacuna** where the [[bone cells|osteocytes]] live. They do not move around, but instead connect to the [[blood vessels]] with little tendrils that spread out through the tiiiiny openings called **canaliculi**. The osteocyte tendrils connect to other cells or the blood vessels via [[gap junction|gap junctions]].
![[canaliculi.png]]
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