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Bone, or osseous tissue, is a connective tissue that has a large amount of two different types of matrix material. There are three types of cells in bone: osteoblasts, osteocytes, and osteoclasts.

(a) osteoblast

The cells that make the bone are called osteoblasts. Osteoblasts are active in making bone for growth and remodeling. Osteoblasts deposit bone material into the matrix and, after the matrix surrounds them, they continue to live, but in a reduced metabolic state as osteocytes.

b. osteocyte

Osteocytes are found in lacunae of the bone. It occupies a small chamber called a lacuna, which is contained in the calcified matrix of bone. Osteocytes derive from osteoblasts, or bone-forming cells, and are essentially osteoblasts surrounded by the products they secreted.

(c) osteoclast

Osteoclasts are active in breaking down bone for bone remodeling, and they provide access to calcium stored in tissues. Osteoclasts are usually found on the surface of the tissue.

d. osteon

Compact bone is organized into subunits called osteons. the osteon is responsible for the strength of the bone, the influx of nutrients into the bone, and waste removal from the bone.