Action of Myofibrils In Muscular Contraction and ATP as an Energy Sourc

Action of Myofibrils In Muscular Contraction and ATP as an Energy Source for Muscular Contraction Abstract: The objective of this research was to determine how myofibrils and ATP are involved and/or altered in muscular contraction. I analyzed the structure of myofibrils and their subunits of myosin and actin. I then determined that myosin shortens actin, carrying out a muscular contraction, by forming cross-bridges between the myosin heads and the actin filaments. I also discovered how ATP is used in muscular contraction and then replaced by undergoing a reaction with PCr. This research is very important to athletes and doctors in order understand how to increase muscular performance and treat muscular diseases, respectively. The human body has an uncountable number of muscle fibers. There are so many, packed so tightly, that it makes it nearly impossible to isolate any small number of cells. In one study, it was determined that the tibialis anterior was made up of 160,000 muscle fibers. [1] The size of this muscle is not particularly impressive and the ?biceps brachii muscle likely contains 3-4 times that number.? [2] Not only that, but human skeletal muscles are always changing how they interact with themselves, and the rest of the body. This is especially apparent in muscular contraction. In fact, it has only been in the last 50 years that we have begun to really understand them, and much of the research that has been done has been conducted on animals that are not humans; one can see the problems that may arise from cutting up a human and examining muscles as they contract. It is important to have at least a rudimentary understanding of these processes for one?s own health purposes, athletic performanc... ...296-305. [5] MacIntosh, B., Gardiner, P., & McComas, A. Skeletal Muscle: Form and Function 2nd Edition. Chpt 11. 2006 [6] Huxley, H. E. The Contractionof muscle. Scientific American 199,67-82. 1958 [7] Currie, David. The Molecular Basis of Muscular Contraction: Hanxon and Huxley?s sliding filament theory of muscle contraction. http://faculty.etsu.edu/currie/muscmolec.htm 2007 Figures Figure 1 Courtesy of www.edcemter.sdsu.edu Figure 2 Courtesy of www.ohioline.osu.edu/sc172/images/sc172_42.jpg Figure 3 Courtesy of www.biomed.miami.edu/pharm/faculty_Szczesna.html Figure 4 Courtesy of: http://www.embl-heidelberg.de/CellBiophys/LocalProbes/motorproteins/myosin.html Figure 5 Courtesy of http://www.edcenter.sdsu.edu Figure 6 Courtesy of http://biology.clc.uc.edu/graphics/bio104/atp.jpg Figure 7 Courtesy of http://staff.jccc.net/pdecell/cellresp/glycolysis.gif