Answer:
The Haversian system, also known as the Haversian canal, is a structural unit in bones that forms the basic functional unit of the osteon. It consists of a central canal (the Haversian canal) surrounded by concentric layers of osteocytes and mineralized matrix. The Haversian canal is lined with endosteum and contains the blood vessels, nerves, and other connective tissue elements that are essential for the nutrition and maintenance of the bone tissue. The Haversian system helps to transfer load from one part of the bone to another, maintain the overall strength and stability of the bone, and allow for the adaptation of bone tissue to changing mechanical demands.