ribonucleic acid, RNA (noun). (biochemistry) a long linear polymer of nucleotides found in the nucleus but mainly in the cytoplasm of a cell where it is associated with microsomes; it transmits genetic information from DNA to the cytoplasm and controls certain chemical processes in the cell.
Osteocytes â mature osteoblasts. Osteoclasts â bone-destroying cells. Compact bone A structural unit of a compact bone is called an osteon (or Haversian system). Osteon â cylindrical structure oriented parallel to bone's long axis.Osteon consists of hollow tubes, one inside the other, called lamella.steocytes â mature osteoblasts. Osteoclasts â bone-destroying cells. Compact bone A structural unit of a compact bone is called an osteon (or Haversian system). Osteon â cylindrical structure oriented parallel to bone's long axis.Osteon consists of hollow tubes, one inside the other, called lamella.
Osteoblasts are the major cellular component of bone. The functional part of bone, the bone matrix, is entirely extracellular (outside of the cells). The bone matrix consists of protein and mineral. The protein is called the organic matrix; it is synthesized first, and then the mineral is added.ndividual cells cannot make bone, and the group of organized osteoblasts together with the bone made by a unit of cells is usually called the osteon; the basis of this is discussed in Organization and ultrastructure of osteoblasts below.