(a(i))[1]
As striated muscle contracts, state the change in the length of the I-band.
(a(ii))[1]
As striated muscle contracts, state the change in the length of the A-band.
(b)[4]
Describe how the sarcoplasmic reticulum’s response to an arriving action potential brings about contraction in striated muscle.
(c)[3]
Glycogen storage disease type V (GSDV) is a metabolic disorder in which stored glycogen cannot be broken down to release glucose, so only small amounts of ATP are made. Individuals with GSDV cannot exercise normally because the shortage of ATP affects how striated muscle functions. With reference to the sliding filament model of muscular contraction, suggest why a lack of ATP affects the functioning of striated muscle.