A: | Muscle bundles are held together by collagenous connective tissue layer called fascicle. |
B: | Sarcoplasmic reticulum of muscle fibre is a store house of calcium ions. |
C: | Striated appearance of skeletal muscle fibre is due to distribution pattern of actin and myosin proteins. |
D: | M line is considered as functional unit of contraction called sarcomere. |
1. | C and D only | 2. | A, B and C only |
3. | B and C only | 4. | A, C and D only |
Which of the following is correct statement ?
1. | Actin and regulatory proteins are located in thin filament. |
2. | Z-lines anchor myosin (thick) filament to the ends of the sarcomere. |
3. | Sarcoplasmic reticulum stores acetylcholine. |
4. | Myosin cross bridges contain calcium binding sites. |