Question

1. what are the forms of graded muscle responses in what differentiates these forms from one another?

2. Explain the significance of the length tension curve for a sarcomere.

Answer 1

1)

solu :

• A graded muscle response allows variation in muscle tension.
• A series of action potential to the muscle fibers is necessary to produce a muscle contraction that can produce work.Normal muscle contraction is most sustained and the input can be modified from the nervous system to produce varying amounts of force.This is called graded response.

2)

solu :

• The length -tension relationship can explain by the sliding filament mechanism of muscle contraction.
• Accordin to this mechanism,during contraction,the amount of tension generated depends on total number of cross-linkage formed due to interaction between actin and myosin molecules.

1. ​​​​​​​At resting length,there is utmost overlap betweenactin and myosin filaments that can lead to maximum tension development.
2. Asthe muscle is stretched beyond this length,overlap between thick and thin filaments decreases progressively and the active tension developed declines proportionately,such that,when there is no overlap,the tension generated becomes nil.
3. On the contrary,when the length becomes less than the resting length,overlap decreases and the tension declines.
4. With extreme reduction in length,the thin filaments overlap each other in the center of the sacromeres so that the binding sites on actin are in the bare area of the thick filaments,producing minimal tension.