Physiology Quiz: Sarcomere - Part 1

(1) The thin filaments of muscle fibers are made of the following protein:

	(A) Actin
	(B) Myosin
	(C) Tubulin
	(D) Albumin
	(E) α-Actinin

(2) The thick filaments of muscle fibers are made of the following protein:

	(A) Actin
	(B) Myosin
	(C) Tubulin
	(D) Albumin
	(E) α-Actinin

(3) Within the muscle sarcomere, at the outer edges of the A band where there is overlap between the thin and thick filaments, each thin filament is surrounded by:

	(A) 1 Thick filament
	(B) 2 Thick filaments
	(C) 3 Thick filaments
	(D) 4 Thick filaments
	(E) 6 Thick filaments

(4) Within the muscle sarcomere, binding of Ca²⁺ to this molecule will lead to the exposure of cross-bridge binding sites.

(5) This protein found within skeletal muscle fibers is thought to be the largest (i.e., number of amino acid residues) known protein.