muscles exam

The functional unit of skeletal muscle is called

sarcomere

Facial muscle that helps you smile (cheekbone to side of mouth)

zygomaticus

Possible causes of muscle fatigue

lack of ATP; lactic acid buildup; Na+ and K+ imbalance; SR/sarcolemma damage affecting Ca2+

Activating more motor units to increase strength

recruitment

Main jaw muscle for chewing

masseter

Primary flexor of the arm (scapula to radius)

biceps brachii

Endurance training increases all EXCEPT

formation of more muscle cells (hyperplasia)

Group of muscle fibers innervated by one neuron

motor unit

Muscle covering front of neck and chin

platysma

Rotator cuff muscle above scapular spine

supraspinatus

Muscle inserting on calcaneus (stand on toes)

gastrocnemius

Ion that allows actin and myosin to bind

calcium

Large superficial back muscle for shoulder movement

trapezius

Muscle lengthens while contracting

eccentric contraction

Neurotransmitter at neuromuscular junction

acetylcholine

Resistance training increases all EXCEPT

formation of more muscle cells (hyperplasia)

Large chest muscle for anterior arm adduction

pectoralis major

Holding weight without moving

isometric contraction