The Sliding Filament Theory: Difference between revisions
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The sliding of myosin and [[Actin|actin ]] | The sliding of myosin and [[Actin|actin filaments]] causes muscles to contract. There are many forms of muscle contraction including contraction of the skeletal [[Muscle|muscle]], the heart and gut peristalsis<ref>Alberts et al, Molecular Biology of the Cell, 5th edition:1026</ref> all of which require the well regulated movement of the [[ATP|ATP]]-dependent sliding filaments. Each [[Sarcomere|sarcomere is]] made up of a highly organised sequence of thick and thin filaments. The thin filaments are mainly made up of actin along with associated proteins<ref>Alberts et al, Molecular Biology of the Cell, 5th edition:1026</ref>. These filaments are all attached by their ends to a structure called a Z disc, the other end reaches parallel into the structure overlapping the thick filaments which are made up of [[Myosin|myosin]], each filament is evenly spaced between the other<ref>Alberts et al, Molecular Biology of the Cell, 5th edition:1026</ref>. Sarcomere shortening is not caused by the contraction or shortening of the actual filaments but by the sliding of the myosin filaments past the actin filaments<ref>Bowness et al, CGP, A2 Level Biology Revision guide:62</ref>. [[Image:Sliding_filament_theory.jpg|The actin filaments slide past the myosin filaments toward the middle of the sarcomere (M line). The result is shortening of the sarcomere and the muscle contracts, however there is no change in filament length.]]<br> | ||
<br><u></u><u>'''References'''</u> | <br><u></u><u>'''References'''</u> | ||
[http://www.ncbi.nlm.nih.gov/books/NBK9961/figure/A1795/?report=objectonly http://www.ncbi.nlm.nih.gov/books/NBK9961/figure/A1795/?report=objectonly] | |||
Revision as of 13:00, 21 November 2011
The sliding of myosin and actin filaments causes muscles to contract. There are many forms of muscle contraction including contraction of the skeletal muscle, the heart and gut peristalsis[1] all of which require the well regulated movement of the ATP-dependent sliding filaments. Each sarcomere is made up of a highly organised sequence of thick and thin filaments. The thin filaments are mainly made up of actin along with associated proteins[2]. These filaments are all attached by their ends to a structure called a Z disc, the other end reaches parallel into the structure overlapping the thick filaments which are made up of myosin, each filament is evenly spaced between the other[3]. Sarcomere shortening is not caused by the contraction or shortening of the actual filaments but by the sliding of the myosin filaments past the actin filaments[4]. 
References
http://www.ncbi.nlm.nih.gov/books/NBK9961/figure/A1795/?report=objectonly