Bone Cell, :) By: Lynnissa Baker.

Function. Osteocytes descend from osteoblasts. They are formed by the incorporation of osteoblasts into the bone matrix. Osteocytes remain in contact with each other and with cells on the bone surface via gap junction-coupled cell processes passing through the matrix via small channels, that connect the cell body-containing a gap with each other and with the outside world. During differentiation from osteoblasts to mature osteocyte the cells lose a large part of their cell organelles. Their cell processes are packed with microfilaments. Osteocytes are actively involved in bone turnover, the osteocyte network is through its large cell-matrix contact surface involved in ion exchange; and osteocytes are the cells of bone and play a pivotal role in functional adaptation of bone.

Function. The osteocyte is the most abundant cell type of bone. There are approximately 10 times as many osteocytes as osteoblasts in adult human bone, and the number of osteoclasts is only a fraction of the number of osteoblasts. Current knowledge of the role of osteocytes in bone metabolism is far behind our insight into the properties and functions of the osteoblasts and osteoclasts. However, the striking structural design of bone predicts an important role for osteocytes in determining bone structure. The role of osteocytes as the cells of bone. Flow of fluid through this seems to mechanically activate the osteocytes, as well as ensure transport of cell signaling molecules, nutrients, and waste products. This concept explains local bone gain and loss—as well as remodeling in response to fatigue damage—as processes supervised by osteocytes. Alignment during remodeling seems to occur as a result of the osteocyte’s sensing different flow patterns around the cutting cone and reversal zone during loading, therefore determining the bone’s structure.

Structure. There are five main types of bone cells in bone tissue. Osteogenic cells respond to traumas, such as fractures, by bone-destroying cells. Osteoblasts synthesize and secrete non- mineralized ground substance and are found in areas of high metabolism within the bone. Osteocytes are mature bone cells made from osteoblasts that have made bone tissue around themselves. These cells maintain healthy bone tissue by secreting enzymes and they also control the calcium release from the bone tissue to the blood. Osteoclasts are large cells that break down bone tissue. They are very important to bone growth, healing, and remodeling. The last type of cells are bone-lining cells. These are made from osteoblasts along the surface of most bones in an adult. Bone-lining cells are thought to regulate the movement of calcium and phosphate into and out of the bone.

Osmosis. Osmosis is the diffusion of water through a semi- permeable membrane. More specifically, it is the movement of water across a semi-permeable membrane from an area of high water concentration to an area of low water concentration. It is a physical process in which a solvent moves, without input of energy, across a semi-permeable membrane separating two solutions of different concentrations. Osmosis releases energy, and can be made to do work for the bone cells.

Cellular Respiration. Cellular respiration, also known as oxidative metabolism, is one of the main ways osteocytes gains useful energy. It is the set of the metabolic reactions and processes that take place in organisms cells to convert biochemical energy from nutrients into ATP, and then release waste products. The reactions involved in respiration are catabolic reactions that involve the oxidation of one molecule of the bone cells and the reduction of another cell.

Photosynthesis. Photosynthesis is a process that converts carbon dioxide into organic compounds, using the energy from sunlight. Photosynthesis occurs in plants, algae, and many species of bacteria. Since it allows them to create their own food. Photosynthesis is vital for life on Earth. As well as maintaining the normal level of oxygen in the atmosphere, nearly all life either depends on it directly as a source of energy, or indirectly as the ultimate source of the energy in their food. As well as energy, photosynthesis is also the source of the carbon in all the bone cells within organisms' bodies.