Multiple Choice
In the sliding filament model of muscle contraction, the myofilaments slide over each other, resulting in the overlapping of actin and __________.
1
views
9. Muscle Tissue
Steps of Muscle Contraction
Multiple Choice
Which of the following allows recoil of the muscle fiber when contraction ends?
A
troponin
B
elastic filaments
C
myosin
D
actin
E
tropomyosin
Verified step by step guidance1
Understand the role of elastic filaments in muscle contraction. Elastic filaments, primarily composed of the protein titin, are responsible for maintaining the structural integrity of the sarcomere and allowing the muscle fiber to return to its resting length after contraction.
Review the structure of a sarcomere, the functional unit of a muscle fiber. The sarcomere is composed of thick filaments (myosin), thin filaments (actin), and elastic filaments (titin).
Consider the function of titin, which is the main component of elastic filaments. Titin acts as a molecular spring, providing passive elasticity to the muscle fiber and helping it recoil after contraction.
Differentiate between the roles of other proteins listed: Troponin and tropomyosin are regulatory proteins involved in muscle contraction, while myosin and actin are contractile proteins that interact to produce muscle contraction.
Conclude that elastic filaments, due to the presence of titin, are responsible for the recoil of the muscle fiber when contraction ends, allowing the muscle to return to its original length.
Related Videos
Related Practice
