(a)[4]
Using Fig. 1.1, name A, B, C and D.
(b)[4]
After a muscle cell is stimulated, calcium ions are released from the sarcoplasmic reticulum. Referring to Fig. 1.1, describe the role of calcium ions in sarcomere contraction.
(c)[2]
When a mammal dies, aerobic respiration stops. The striated muscles contract and remain contracted for a few hours after death. Suggest why the muscles stay contracted for a few hours.