Question

Haversian system present in the long bones contain
A)An artery and vein.
B)A nerve and lymphatic vessel
C)Few osteoblast
D)All of the above

Answer 1

Hint: Haversian canals are found within the osteons and are typically arranged along the long axis of the bone in parallel to the surface.

Complete answer:
The morphological and the functional unit of the bone is the Haversian system. Haversian or central canals are connected by Volkmann's or perforating or transverse canals. Formally the Haversian and Volkmann's canals are nutrient and perforating canal which is seen in Terminologia Histologica. The canals possess a concentric lamellar association and are of equivalent size. The bone is vascularized by vessels which penetrate the matrix from the periosteum.

The microstructure of the dense bone is significant to bone remodeling and modification in pathologic conditions. Consequently knowledge of the microstructure of dense bone which includes the Haversian system and is important for understanding remodeling activity, distribution analysis, the pathogenesis of osteoporosis, and other mechanisms. On the other hand, many studies of the Haversian system have focused only on the canals themselves owing to methodology limitations associated with cross-sectional histology and microcomputed tomography fairly than on the general canal system or the spatial relationships among the two types of canals. Understanding of the whole composition of the Haversian system as well as the ingredient canals themselves is very important when investigating changes relative to the normal system.

The Haversian canal is a central canal within the Haversian system which is a system of canals within the compact bone. Haversian canals take place in the centre of the compact bone and contain blood vessels, connective tissues, nerve fibres and lymphatic vessels. The marrow in the body of long bone is supplied by one large artery which enters the body at the nutrient foramen and perforates indirectly to the compact structure. The medullary or nutrient artery is accompanied by one or two veins that sends branches aloft and down which ramify in the medullary membrane and give branches to the adjacent canals.

Hence, the correct answer is option (B)

Note: The main function of haversian canal allows bone to get oxygen and nutrition without being highly vascular. They also communicate with bone cells by the use of special connections or the canaliculi.