Understanding Sliding Filament Theory - Biology

The sliding filament theory describes the mechanism that allows muscles to contract. According to this theory, myosin (a motor protein) binds to actin. The myosin then alters its configuration, resulting in a "stroke" that pulls on the actin filament and causes it to slide across the myosin filament. The overall process shortens the sarcomere structure, but does not change the actual length of either filament.

In the sliding filament theory, myosin heads attach to an actin filament, bend to pull the actin filaments closer together, then release, reattach, and pull again. Energy from ATP is required for the myosin head to release from the actin filament—otherwise the myosin heads would remain in the same place, and the muscle would not contract. Even though the filaments are moving, the filaments themselves never actually get shorter or longer.

When ATP stores are depleted, myosin becomes incapable of detaching from actin, and the muscle remains in a taut, flexed state. This is the cause of rigor mortis.

The correct answer is ATP and calcium ions. Myosin head activation to form a cross-bridge with actin requires ATP, and the cleavage of ATP to ADP + Pi contracts the myosin head and pulls the actin. Calcium is required to expose actin binding sites for myosin in conjunction with troponin.

The myosin head will hydrolyze the . Being bound to ADP, this allows the myosin head to form crossbridges by binding to actin. As ADP detaches from the myosin head, the head will produce the power stroke motion, where the myosin heads will rotate toward the sarcomeres. The myosin head will be locked in this position, attached to the actin, until another ATP molecule comes and attaches to the myosin head. This will allow the head to detach from actin and reorient itself to complete the process again.

Sarcomeres are composed of thick and thin filaments. The thin filament is composed of polymerized actin, while the thick filament is composed of myosin. Titin is a protein that spans the full range of the sarcomere, and is involved in stability and elasticity in the muscle. Collagen is not a primary component of sarcomeres.

The sliding filament theory describes the mechanism that allows muscles to contract. According to this theory, myosin (a motor protein) binds to actin. The myosin then alters its configuration, resulting in a "stroke" that pulls on the actin filament and causes it to slide across the myosin filament. The overall process shortens the sarcomere structure, but does not change the actual length of either filament.

In the sliding filament theory, myosin heads attach to an actin filament, bend to pull the actin filaments closer together, then release, reattach, and pull again. Energy from ATP is required for the myosin head to release from the actin filament—otherwise the myosin heads would remain in the same place, and the muscle would not contract. Even though the filaments are moving, the filaments themselves never actually get shorter or longer.

When ATP stores are depleted, myosin becomes incapable of detaching from actin, and the muscle remains in a taut, flexed state. This is the cause of rigor mortis.

The correct answer is ATP and calcium ions. Myosin head activation to form a cross-bridge with actin requires ATP, and the cleavage of ATP to ADP + Pi contracts the myosin head and pulls the actin. Calcium is required to expose actin binding sites for myosin in conjunction with troponin.

The myosin head will hydrolyze the . Being bound to ADP, this allows the myosin head to form crossbridges by binding to actin. As ADP detaches from the myosin head, the head will produce the power stroke motion, where the myosin heads will rotate toward the sarcomeres. The myosin head will be locked in this position, attached to the actin, until another ATP molecule comes and attaches to the myosin head. This will allow the head to detach from actin and reorient itself to complete the process again.

Sarcomeres are composed of thick and thin filaments. The thin filament is composed of polymerized actin, while the thick filament is composed of myosin. Titin is a protein that spans the full range of the sarcomere, and is involved in stability and elasticity in the muscle. Collagen is not a primary component of sarcomeres.

The sliding filament theory describes the mechanism that allows muscles to contract. According to this theory, myosin (a motor protein) binds to actin. The myosin then alters its configuration, resulting in a "stroke" that pulls on the actin filament and causes it to slide across the myosin filament. The overall process shortens the sarcomere structure, but does not change the actual length of either filament.

In the sliding filament theory, myosin heads attach to an actin filament, bend to pull the actin filaments closer together, then release, reattach, and pull again. Energy from ATP is required for the myosin head to release from the actin filament—otherwise the myosin heads would remain in the same place, and the muscle would not contract. Even though the filaments are moving, the filaments themselves never actually get shorter or longer.

When ATP stores are depleted, myosin becomes incapable of detaching from actin, and the muscle remains in a taut, flexed state. This is the cause of rigor mortis.

The correct answer is ATP and calcium ions. Myosin head activation to form a cross-bridge with actin requires ATP, and the cleavage of ATP to ADP + Pi contracts the myosin head and pulls the actin. Calcium is required to expose actin binding sites for myosin in conjunction with troponin.

The myosin head will hydrolyze the . Being bound to ADP, this allows the myosin head to form crossbridges by binding to actin. As ADP detaches from the myosin head, the head will produce the power stroke motion, where the myosin heads will rotate toward the sarcomeres. The myosin head will be locked in this position, attached to the actin, until another ATP molecule comes and attaches to the myosin head. This will allow the head to detach from actin and reorient itself to complete the process again.

Sarcomeres are composed of thick and thin filaments. The thin filament is composed of polymerized actin, while the thick filament is composed of myosin. Titin is a protein that spans the full range of the sarcomere, and is involved in stability and elasticity in the muscle. Collagen is not a primary component of sarcomeres.

The sliding filament theory describes the mechanism that allows muscles to contract. According to this theory, myosin (a motor protein) binds to actin. The myosin then alters its configuration, resulting in a "stroke" that pulls on the actin filament and causes it to slide across the myosin filament. The overall process shortens the sarcomere structure, but does not change the actual length of either filament.

In the sliding filament theory, myosin heads attach to an actin filament, bend to pull the actin filaments closer together, then release, reattach, and pull again. Energy from ATP is required for the myosin head to release from the actin filament—otherwise the myosin heads would remain in the same place, and the muscle would not contract. Even though the filaments are moving, the filaments themselves never actually get shorter or longer.

When ATP stores are depleted, myosin becomes incapable of detaching from actin, and the muscle remains in a taut, flexed state. This is the cause of rigor mortis.

The correct answer is ATP and calcium ions. Myosin head activation to form a cross-bridge with actin requires ATP, and the cleavage of ATP to ADP + Pi contracts the myosin head and pulls the actin. Calcium is required to expose actin binding sites for myosin in conjunction with troponin.

The myosin head will hydrolyze the . Being bound to ADP, this allows the myosin head to form crossbridges by binding to actin. As ADP detaches from the myosin head, the head will produce the power stroke motion, where the myosin heads will rotate toward the sarcomeres. The myosin head will be locked in this position, attached to the actin, until another ATP molecule comes and attaches to the myosin head. This will allow the head to detach from actin and reorient itself to complete the process again.