Tetanic contraction: Difference between revisions
Fixed the references (please watch the 'how to ref' video). Put 2+ as superscript (please learn how to use the editor). Added a lot of links. Removed a heading that was not needed. |
No edit summary |
||
| Line 1: | Line 1: | ||
Tetanic muscle contraction is a type of muscle contraction which occurs in [[ | Tetanic muscle contraction is a type of muscle contraction which occurs in [[Skeletal muscle|skeletal muscles]], resulting in a stronger prolonged contraction. Tetanic contraction occurs through summation of [[Action potentials|action potentials]] travelling into a [[Muscle fibres|muscle fibre]]<ref>Muscle Contraction. http://michaeldmann.net/mann14.html (accessed 23/11/16).</ref>. As the frequency of the action potentials increases, the muscle has less time to relax and remove the [[Calcium|calcium]] (Ca<sup>2+</sup>)<sup> </sup>[[Ions|ions]] in the sarcoplasm which initiated muscle contraction, through the binding to troponin, causing the [[Myosin|myosin]] binding site to be revealed. Once a given frequency has been reached, the muscle fibre doesn't have time to remove all of the Ca<sup>2+</sup> in the [[Sarcoplasmic reticulum|sarcoplasm]] before the next action potential, resulting in Ca<sup>2+</sup> remaining in the sarcoplasm. As some Ca<sup>2+</sup> remains in the sarcoplasm, when the next action potential arrives, more Ca<sup>2+</sup> is released from the [[Sarcoplasmic reticulum|sarcoplasmic reticulum]], resulting in a higher amount of Ca<sup>2+</sup> in the sarcoplasm than in the first action potential. This results in a stronger contraction as more Ca<sup>2+</sup> is present, so more myosin binding sites are unveiled, therefore more [[Myosin-actin cross bridges|myosin-actin cross bridges]] can be formed<ref>Ca2+ Regulation of Muscle Contraction. https://courses.washington.edu/conj/bess/muscle/calciumreg.html (accessed 23/11/16).</ref>. | ||
=== References === | === References === | ||
<references /> | |||
Latest revision as of 13:40, 23 November 2016
Tetanic muscle contraction is a type of muscle contraction which occurs in skeletal muscles, resulting in a stronger prolonged contraction. Tetanic contraction occurs through summation of action potentials travelling into a muscle fibre[1]. As the frequency of the action potentials increases, the muscle has less time to relax and remove the calcium (Ca2+) ions in the sarcoplasm which initiated muscle contraction, through the binding to troponin, causing the myosin binding site to be revealed. Once a given frequency has been reached, the muscle fibre doesn't have time to remove all of the Ca2+ in the sarcoplasm before the next action potential, resulting in Ca2+ remaining in the sarcoplasm. As some Ca2+ remains in the sarcoplasm, when the next action potential arrives, more Ca2+ is released from the sarcoplasmic reticulum, resulting in a higher amount of Ca2+ in the sarcoplasm than in the first action potential. This results in a stronger contraction as more Ca2+ is present, so more myosin binding sites are unveiled, therefore more myosin-actin cross bridges can be formed[2].
References
- ↑ Muscle Contraction. http://michaeldmann.net/mann14.html (accessed 23/11/16).
- ↑ Ca2+ Regulation of Muscle Contraction. https://courses.washington.edu/conj/bess/muscle/calciumreg.html (accessed 23/11/16).