5.9k views
3 votes
Power stroke (myosin head bends) coupled with the release of ADP and phosphate, ATP hydrolyzed to ADP and Phosphate and the Myosin head changes configuration then binds to the actin filament, ATP binds to bent myosin and detaches myosin from actin filament, Myosin and ATP are unbound and ben

2 Answers

5 votes

Answer:

Refer below.

Step-by-step explanation:

ATP restricting makes myosin discharge actin, permitting actin and myosin to disengage from one another. After this occurs, the recently bound ATP is changed over to ADP and inorganic phosphate, Pi. The catalyst at the coupling site on myosin is called ATPase. The vitality discharged during ATP hydrolysis changes the point of the myosin head into a "positioned" position. The myosin head is then in a situation for additional development, having potential vitality, yet ADP and Pi are as yet joined. In the event that actin restricting locales are secured and inaccessible, the myosin will stay in the high vitality arrangement with ATP hydrolyzed, yet at the same time joined.

On the off chance that the actin restricting destinations are revealed, a cross-extension will shape; that is, the myosin head traverses the separation between the actin and myosin particles. Pi is then discharged, permitting myosin to use the put away vitality as a conformational change. The myosin head advances toward the M line, pulling the actin alongside it. As the actin is pulled, the fibers push roughly 10 nm toward the M line. This development is known as the force stroke, as it is the progression at which power is created. As the actin is pulled toward the M line, the sarcomere abbreviates and the muscle contracts.

At the point when the myosin head is "positioned," it contains vitality and is in a high-vitality arrangement. This vitality is consumed as the myosin head travels through the force stroke; toward the finish of the force stroke, the myosin head is in a low-vitality position. After the force stroke, ADP is discharged; nonetheless, the cross-connect shaped is still set up, and actin and myosin are bound together.

User Espenhw
by
4.1k points
4 votes

Answer:

Power stroke (myosin head bends) coupled with the release of ADP and phosphate

Step-by-step explanation:

Muscle contraction results from myosin heads adhering to actin and attracting it inwards. It uses ATP. Myosin adhers to actin at a binding site of its globular actin protein and adheres at another binding site for ATP (hydrolyzed ATP to ADP, Pi and energy)

ATP binding prompts myosin to detach from actin, ATP is changed to ADP and inorganic phosphate, Pi by ATPase. The energy formed at this process orientates myosin head to a “cocked” direction.

The myosin head goes in the direction of the M line, holding the actin with it in the process causing the filaments to orientate nearly 10 nm in the direction of the M line--- power stroke (force is produced), the sarcomere reduces in length and the muscle contracts.

Note: The power stroke is seen when ADP and phosphate disattaches itself from the myosin head.

At the terminal point of the power stroke, the myosin head as low-energy, followed by ADP release.

The attached image shows the cross-bridge muscle contraction cycle, which is activated by Ca2+ sticking to the actin active site. And how actin moves in relation to myosin.

Power stroke (myosin head bends) coupled with the release of ADP and phosphate, ATP-example-1
User Gmoon
by
3.9k points