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Question
Write the differences between Actin and Myosin.
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Solution
| Actin | Myosin | |
| 1. | Found in both A and I bands. | Found exclusively in A band of sarcomere. |
| 2. | Thinner (0.005 mm), but shorter (2-2.6 mm) than myosin filaments. | Thicker (0.01 mm) and longer (4.5 mm) than actin filaments. |
| 3. | Cross bridges are absent, resulting in a smooth surface. | Cross bridges are present, resulting in a rough surface. |
| 4. | They are more numerous than myosin filaments, with six surrounding each one. | Fewer than actin filaments. |
| 5. | Free at one end and linked to the Z-line at the other end. | Free at both ends. |
| 6. | Consists of three proteins: actin, tropomysin, and troponin. | Consists of two proteins: myosin and meromyosin. |
| 7. | Slide into the H zone during muscule contraction. | Do not slide during muscle contractions. |
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