ATPase activity is found in:
| 1. | Myosin head | 2. | Myosin tail |
| 3. | G-Actin | 4. | Troponin |
During relaxation of a skeletal muscle:
| 1. | Calcium ions that are bound to troponin C now bind to troponin A |
| 2. | Cross bridge formation between myosin head and actin takes place |
| 3. | The A band of the sarcomere lengthens |
| 4. | Calcium ions are pumped back to the sarcoplasmic cisternae |
During muscle contraction, when the myosin head releases ADP and iP it:
1. forms cross bridge with actin
2. pulls actin towards M-line
3. goes back to its relaxed state
4. gets detached from the cross bridge
Which of the following masks the active sites on actin when a skeletal muscle is relaxed?
| 1. | Tropomyosin | 2. | Troponin |
| 3. | Calmodulin | 4. | Ubiquitin |