Muscle, basic functions

Fig. 9.11. Muscle basic functions and antagonists change of an angle between two skeletal elements...

Fig. 9.12. Muscle basic functions and antagonists, a Direct drive (dragonfly), b indirect drive (fly, bee)...

Fig. 9.13. Muscle, basic functions and antagonists. Change of areas and lumina a enlargement of chromatophone, b enlargement of lumen, c diminution of lumen...

Another informative aspect of this analogy is the issue of how to deal with the treatment of hierarchical level. Clearly, the chemical elements are made up of smaller particles (e.g., protons, neutrons, and electrons). Physicists have identified even smaller, more elusive entities such as bosons, quarks, and so on. Do we need to consider items at this lowest level of abstraction each time a simple compound such as hydrochloric acid is made Likewise, the term basic in basic elements of performance is clearly relative and requires the choice of a particular hierarchical level of abstraction for the identification of systems or basic functional units a level which is considered to be both natural and useful for the purpose at hand, lust as it is possible but not always necessary or practical to map chemical elements down to the atomic particle level, it is possible to consider mapping a basic element of performance (see latter) such as elbow flexor torque production capacity down to the level of muscle fibers, biochemical reactions at neuromuscular junctions, and so forth. 

It is the arteries that provide the blood supply to the body, specifically to the organs and tissues. Should the arteries suffer from some pathology, the patient becomes exposed to impaired blood flow, lack of adequate oxygen supply and nutrients to muscles, compromised function of tissues and organs, and the risk of embolization and aneurysmal disease, which can be life threatening. Basic classification of pathologies is as follows. 

The importance of food muscle proteins lies mainly in the fact that these are a source of amino acids, some of them essential for health. Proteins are the main structural and functional components of many foods and play an essential role in their sensory characteristics and technological properties, particularly in muscle-based foods (meat and fish). Technological (functional) properties are all those physicochemical properties of proteins that affect their behaviour (in meat or fish matrixes) during the preparation, processing, storage and consumption of foods and which affect their various quality attributes. Muscle proteins influence many basic functional properties of muscle-based... 

Pathogenesis of MH is not completely understood. Skeletal muscle, however, is the one tissue in MH with proven abnormalities, and it is further thought that the basic defect that causes the syndrome lies in the calcium regulation system found within the myoplasm. For example, calcium transport function appears to be decreased in the sarcoplasmic reticulum, mitochondria, and sarcolemma. Thus, the suggestion has been made that MH is characterized by a generalized membrane defeet. 

Muscle, whose structure and function are discussed in Chapter 19, develops in response to four members of the myoD family. These include myoD, myogenin, myf5, and MRF4.417-419 All are muscle-specific transcription factors of the basic helix -loop -helix class. An unusual aspect of muscle development is formation of multinucleate myotubes (muscle fibers p. 1096)420 Apoptosis plays an important role in muscle development and can present significant complications in damaged cardiac muscle.421 Defects in several developmental control genes are responsible for congenital heart diseases.422... 

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