What are the steps in sliding filament theory?

Answer 1

Before contraction:

1) no nerve impulse to myoneural junction.

2) Ca++ in the sarcoplasmic reticulum

3) combining of actin and myosin is prevented by a tropomyosin-troponin complex that attatches to the actin.

Contraction:

1) an action potential (nerve impulse) travels along a neural axon to a myoneural junction (synapse)

2) Acetylcholine (neurotransmitter) is released from the synaptic vesicles of the neuron.

3) acetylcholine diffuses over into the sacrolemma and the t-tubules.

4) Ca++mis released from the sarcoplasmic reticulum.

5) the Ca++ then binds to the actin degrading the tropomyosin-troponin complex to expose myosin attatchment sights

6) the heads of the myosin myofilaments attatch to the exposed attatchment sights on actin filament

7) ATP binds to the heads of the myosin filaments. breakdown of the ATP to ADP+p releases energy and causes a bending of myosin heads.

8) another ATP binds to the myosin head causing it to release the actin filament then attatch again with the head unbent. again the ATP breaks down and the process continues.

To relax:

1) nerve impulse stops

2) active transport returns Ca++ to the sarcoplasmic reticulum

3) ATP's are reformed (ADP+P+energy=ATP)

4) Tropomyosin-troponin complex reforms causing the myosin to release the actin

5) when the filaments release each other they slide back to the resting position.

Answer 2

The sliding filament theory is a model for muscle contraction that involves the actin and myosin filaments that make up the sarcomere sliding past each other.

Here is a fairly basic overview:

1. ATP hydrolyzes, energizing the heads of the myosin filaments.

2. The myosin heads attach to the binding sites of the actin filaments.

3. A "power stroke" occurs, in which the filaments slide past each other.

4. The next ATP binds to the myosin head thus detaching it from the actin filament.

Answer 3

The sliding filament theory is the theory used to explain how muscles move. How muscles extract is unique to any other part of the body and muscles can be unique from each other especially after injury.

Answer 4

The sliding filament theory is one of the theories used to explain how muscles contract. The muscle contracts when the muscles are shortened. This occurs when the thick and thin filaments overlap by sliding past each other. The filament themselves are not shortened.

Inside a sarcomere during contraction, the A band stays the same length while the I band, H zone, and sarcomere becomes shortened. The sliding movement occurs due to cyclical formation and the breaking of cross bridges. This is known as the crossbridge cycle.

Answer 5

The sliding filament theory starts off with two tiny fibres called myosin and actin. These overlap and slide past eachother, covered in collagen. These are provided energy by ATP

Answer 6

ATP provides the myosin heads with energy in order to form cross bridges with the tropomyosin on the actin