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.
Bones make up the human skeletal system and are used to support the body and help provide movement. They are made up of two types of bone tissue: spongy and compact. These tissues differ in how dense the bone is, or how tightly the cells are packed together.Compact bone accounts for more than 75 percent of all bone matter in the body when measured by weight.lat bones often have two thin, parallel layers of compact bone, with spongy bone inside. These are often curved bones and include the bones of the skull. Irregular bones do not fit into any of the other shape categories, so they are grouped together.