<prompt> Synol fluid - all are true except :Secreted by Type A cellsFollows non newtonian fluid kineticsContains hyaluronic acidViscosity is variable  <response>: Secreted by Type A cells Ref: Tureks Ohopaedics 6e, p 152; Grays 40e, p 100; Biofluid Mechanics by Jagannath Mazumdar 2004; p 79-83. Type A synol cells are macrophage-like cells. They synthesize and release lyric enzymes and phagocytose joint debris. These cells are not considered to secrete synol fluid. Synol fluid: Is a plasma transudate from synol capillaires hyaluronic acid- protein complex mucin secreted by Type B synol cells cells 60-100 cellsml; mainly lymphocytes and monocytes The viscous and lubricating propey of the synol fluid is attributed to hyaluronic acid. Synol membrane has two types of cells? Type A cells Type B Cells Less in number Predominant cells Macrophage like Fibroblast like Synthesize release lytic Synthesize secrete hyaluronic acid enzymes glycoproteins of synol fluid Phagocytose joint debris Have abundant rough ER Have a prominent Golgi apparatus and little rough ER Synol fluid is a Non-newtonian, thixotropic fluid A Newtonian fluid is one which follows the Newtonian friction law i.e. its viscosity remains constant with agitation or varying shear rate viscosity is only affected by temperature changes. Examples of Newtonian fluid are: water, oils, gases, mercury, alcohol etc. A Non-Newtonian fluid is one that does not follow the Newtonian friction law. Its viscosity changes with agitation or varying shear rate. A Non-Newtonian fluid can be Thixotropic or Rheopectic. Thixotropic is one whose viscosity decreases with agitation or varying shear rate. Thus thixotropic fluid are thick viscous under normal conditions, but become thin, less viscous over time when shaken, agitated, or otherwise stressed. Eg. Synol fluid, ketchup. Rheopectic is one whose viscosity increases with agitation or varying shear rate. Eg. gypsum pastes, printers inks, and some lubricants. Synol fluid has thixotropic propeies. Its viscosity decreases with increase in the rate of movement, thus it is able to provide better lubrication to the joints. 