Final Answer:
The cyclic movement of Myosin II head on the actin filament: 1. Attached, 3. Cocked. Both Options 1 and 3 are answers.
Step-by-step explanation:
The movement of Myosin II head on the actin filament involves a cyclic process that can be described as follows: 1. Myosin is "attached" to actin, forming a cross-bridge. This is followed by a conformational change, leading to the "released" state. Next, myosin transitions to the "cocked" position, storing energy from ATP hydrolysis.
The "force-generating" step releases this stored energy, causing the power stroke and filament sliding. The cycle restarts as myosin reattaches, returning to the "attached" state.
Options 1 and 3 are answers.