II.I How it is use?
Muscle contraction requires the use of ATP molecules. Indeed, muscle cells are composed of contractile elements: sarcomeres. Muscle contraction is due to the slippage of myosin fibers on the actin fibers. For this, the head of the myosin binds to the troponin site of the actin filament. Then, an ATP molecule will bind to myosin to separate actin and myosin and thus allow its attachment to the neighboring troponin site due to hydrolysis of ATP in ADP + Pi.
This creates a slippage of myosin fibers on the actin fibers and allows for muscle contraction.
However, one molecule: tropomyosin binds to the troponin sites present on the actin filaments and thus prevents attachment of myosin fibers to the actin fibers:this allows muscle relaxation. In order …show more content…
This entry of calcium is due to the reception of a nervous signal.
A large amount of ATP must therefore be synthesized rapidly and continuously in order to allow muscle contraction.
During a physical effort, the first system implemented is the anaerobic system. It includes the use of ATP already present in the muscles which allows 2 seconds of muscle contraction, as we saw before in the introduction. Then hydrolysis of phosphocreatine allows 30 seconds of contraction and regenerates some ATP. However, muscle requires continuous production of
ATP throughout the duration of physical exercise. There is therefore another anaerobic means: anaerobic glycogenolysis. It is placed at the beginning of the effort and allows the formation of 3 molecules of ATP from a molecule of glycogen and forms 2 molecules of lactic acid which will hydrolyze in protons H + and anion lactate . During intense and short-term exercise, when proton transport shuttle systems begin to be exceeded, H + ions by combining with pyruvic acid form lactic acid, which causes accumulation of the lactate in the cytosol .In addition, when exercise increases in intensity and duration an ammonium
Muscle contraction requires the use of ATP molecules. Indeed, muscle cells are composed of contractile elements: sarcomeres. Muscle contraction is due to the slippage of myosin fibers on the actin fibers. For this, the head of the myosin binds to the troponin site of the actin filament. Then, an ATP molecule will bind to myosin to separate actin and myosin and thus allow its attachment to the neighboring troponin site due to hydrolysis of ATP in ADP + Pi.
This creates a slippage of myosin fibers on the actin fibers and allows for muscle contraction.
However, one molecule: tropomyosin binds to the troponin sites present on the actin filaments and thus prevents attachment of myosin fibers to the actin fibers:this allows muscle relaxation. In order …show more content…
This entry of calcium is due to the reception of a nervous signal.
A large amount of ATP must therefore be synthesized rapidly and continuously in order to allow muscle contraction.
During a physical effort, the first system implemented is the anaerobic system. It includes the use of ATP already present in the muscles which allows 2 seconds of muscle contraction, as we saw before in the introduction. Then hydrolysis of phosphocreatine allows 30 seconds of contraction and regenerates some ATP. However, muscle requires continuous production of
ATP throughout the duration of physical exercise. There is therefore another anaerobic means: anaerobic glycogenolysis. It is placed at the beginning of the effort and allows the formation of 3 molecules of ATP from a molecule of glycogen and forms 2 molecules of lactic acid which will hydrolyze in protons H + and anion lactate . During intense and short-term exercise, when proton transport shuttle systems begin to be exceeded, H + ions by combining with pyruvic acid form lactic acid, which causes accumulation of the lactate in the cytosol .In addition, when exercise increases in intensity and duration an ammonium