Bones

===Bones are any of the hard pieces, with whitish tissue making up the skeleton in human vertebrates. Spongy bone is one of the two types of osseous tissues that form bones. Also known as Cancellous bone. Compact bone serves as a function to move and support, protects various organs of the body, it produces red and white blood cells, as well as storing minerals. Periosteum is a dense layer of vascular connective tissue enveloping bones except the surfaces of the joints. Bone marrow is soft, spongy-like tissue in the center of bones. It is responsible for blood cells and platelet production. Osteocyte is a bone cell. It forms when an osteoblast becomes embedded in the matrix it has secreted. Artery is a blood vessel that carries blood from the heart to the body. Vein is a blood vessel that carries blood to the heart. Haversian canal is any of the minute tubes that form a network in the bone, it contains blood vessels.===