29 21. Which of the following become connected by myosin cross-bridges during muscle contraction? A) thin filaments and thick filaments B) thick filaments and titin filaments C) z disks and actin filaments D) thick filaments and t-tubules. E) thin filaments and t-tubules 22. A single motor neuron together with all the muscle fibers it innervates is called: A) an end foot. (B) an end plate. C) a motor unit. D) a dermatome. E) none of the above 23. The type of contraction in which the muscle fibers do not shorten is called: A) tetany. B) treppe. C) concentric. D) isotonic. E) isometric. MacBook P 24. The names of the muscles can indicate all of the following, except: A) the angle of the muscle fascicles relative to the long axis of the body. B) the action of the muscle. C) the location of the muscle. D) structural characteristics of the muscle. E collagen content of the muscle. 25. In the human body, A) bones B) joints C) muscles D) internal organs E) tendons 27. In a A) convergent B) parallel C) straight D) pennate E) circular function as fulcrums. 26. A muscle that assists the muscle that is primarily responsible for a given action is a(n): (A) agonist. B) antagonist. C) synergist. D) originator. E) levator. muscle, the fascicles are concentrically arranged around an opening. de FI S