sliding filament theory Flashcards
what does the action potential do once it has reached the muscle cells
depolarises the sarcolemma
what does the depolarisation of the sarcolemma cause
the myosin and actin filaments to slide over each other
what does the sarcomeres contracting cause
the muscle fibres to contract which then makes the whole muscle contract
what happens after the muscle contracts
the sarcomeres relax, the filaments slide back over each other and the muscle relaxes
why do the myosin filaments have globular heads
they move back and forth which allows actin and myosin filaments to slide over each other in muscle contraction
on the myosin head what do the two binding sites bind to
one binds to actin and one binds to ATP
what is the binding site for the myosin heads on the actin filament called
actin myosin binding site
what is tropomyosin
a protein located on the actin filaments
what is the role of tropomyosin
blocks the actin myosin binding site when muscle fibres are at rest
when is aerobic respiration used
mainly used for extended periods of low intensity muscle use
when is anaerobic respiration used
short periods of high intensity muscle use
what can a build up of lactate in the muscles cause
fatigue
what is phosphocreatine
a molecule that can supply ATP for muscle contraction
what does phosphocreatine do
during intense muscular effort it donates phosphate to ADP to produce ATP. The ATP produced is used to sustain muscle contraction
what can ATP do during low periods of muscle activity
it can be used to phosphorylate creatine back into phosphocreatine process is anaerobic
