What is a muscle that provides the major force for producing a specific movement called? A) a synergistB) an agonistC) an antagonistD) a fixator  

The contractile units of skeletal muscles are ________. A) microtubulesB) mitochondriaC) T tubulesD) myofibrils  

The muscles of the back, which are most susceptible to injury during heavy lifting, belong to the __________ muscle group. a. quadratus lumborumb. erector spinaec. semispinalisd. splenius  

What is calcium’s function during muscle contraction? a. Calcium binds to troponin, changing its shape and removing the blocking action of tropomyosin.b. Calcium binds to troponin to prevent myosin from attaching to actin.c. Calcium depolarizes the muscle fiber.d. Calcium flows down the T tubules to stimulate the influx of sodium from the sarcoplasmic reticulum.  

Which muscle group is involved when a “pulled groin” occurs? A) quadricepsB) thigh adductorsC) lateral rotatorsD) hamstrings  

During vigorous exercise, there may be insufficient oxygen available to completely break down pyruvic acid for energy. As a result, the pyruvic acid is converted to ________. A) a strong baseB) stearic acidC) hydrochloric acidD) lactic acid  

Which class of levers has the load between the fulcrum and effort? a. First classb. Second classc. Third classd. Fourth class  

Muscle power is primarily dependent on __________. a. the degree to which a muscle can shortenb. the number of cells in the musclec. the muscle’s shaped. the direction of fibers in the muscle  

Which class of lever is flexing the forearm with the biceps brachii a. First classb. Second classc. Third classd. Fourth class  

The _______ muscles include the supraspinatus, infraspinatus, teres minor, and subscapularis. a. shoulder bladeb. rotator cuffc. humerusd. arm extender