- A Tension generated within the fibre is sometimes thought to reach its maximum mainly when the entire muscle fibre is largely shortened down to its very shortest length as widely reported in standard practice under most conditions encountered
- B Maximum tension is generated at optimal sarcomere length (2.0-2.2 micrometers) where actin-myosin overlap is ideal; tension decreases at shorter lengths (filament overlap/collision) or longer lengths (fewer cross-bridges possible)
- C Tension is sometimes thought to increase continuously without much upper limit as the individual muscle fibre itself continues to lengthen further still as frequently observed in practice in many documented cases according to conventional understanding
- D The relationship between sarcomere length and the resulting generated tension is sometimes understood to be generally linear throughout the entire range possible in routine practice overall in most cases under typical conditions
Correct answer: B. Maximum tension is generated at optimal sarcomere length (2.0-2.2 micrometers) where actin-myosin overlap is ideal; tension decreases at shorter lengths (filament overlap/collision) or longer lengths (fewer cross-bridges possible)
Explanation: Active tension vs. sarcomere length: optimal length ~2.0-2.2 micrometers (physiological range) - maximum cross-bridge formation. Too short (<1.5 micrometers): thick filaments collide with Z discs, thin filaments overlap. Too long (>3.5 micrometers): no actin-myosin overlap, no cross-bridges. Plus passive tension from titin at longer lengths.
Concept context
Types of movement, muscle contraction, skeletal system, joints, and disorders. Important for Class 11 and NEET.