| Term | Definition |
| sarratus | sawtoothed |
| z-disc | protein backbone that anchors actin filaments |
| fascicles | surrounded by perimysiium and bundled into the muscle |
| pollicis | thumb |
| contraction | what muscle cells are specialized for |
| adductor | adducts |
| mastoid | mastoid process |
| sarcoplasm | filled with myofibrils and contain sarcomeres |
| sarcomeres | the unit of contraction of the myofibrils of the muscle |
| muscle fiber | a skeletal muscle cell |
| intermedium | middle |
| brachio | upper arm |
| synergist | secondary muscles that bring about the desired movement. assists the prime mover |
| exocytosis | when ACh is released across the synapse |
| muscle fibers | only shorten to produce movement |
| tendons | anchor muscle to bone and other muscles |
| motor nerve | end at each muscle fiber |
| epimysium | connective tissue covering that surrounds muscles as a whole and binds all muscle fibers together |
| maximus | largest |
| action | the movement a muscle causes when it contracts |
| synapse | the junction between the axon terminal and the muscle fiber sarcolemma |
| prime mover (protagonist) | the primary muscle that brings about the desired movement |
| abductor | abducts |
| upper extremity | brachialis, biceps brachii, triceps brachii, brachioradialis, hand and digit extensors, and hand and digit flexors |
| belly | the thick middle part of a muscle |
| femoris | femur |
| myofibrils | long protein bundles that fill the sarcoplasm of a muscle fiber |
| tintin filaments | protein that anchors myosin to the z-disc |
| superficialis | superficial |
| T-Tubules | tubes that allow signals to travel into the cell |
| flexor | flexes |
| muscular system | includes the skeletal muscles and accessory structures |
| rectus | straight |
| sarcoplasm | special name for cytoplasm of muscle cell |
| thermogenesis | heat production from normal muscle metabolism |
| sarcoplasmic reticulum | stores calcium ions, ER of muscle cell |
| electrical impulse | ACH causes this in the sarcolemma |
| heads | in muscles with more than one belly |
| minor | small |
| major | large |
| origin | where the muscle originates, usually the more stationary of the two ends |
| calf | gastrocnemeus, soleus and plantaris |
| contraction | when myosin binds to actin |
| medialis | medial |
| actin filaments | thin contractile proteins that interact with myosin |
| shoulder and back | deltoid, pectoralis major, serratus anterior, latissimus dorsi, and trapezius |
| myosin filaments | thicker contractile proteins |
| biceps | 2 heads |
| hallicus | big toe |
| longus | long |
| minimus | smallest |
| plantaris | 25% of population does not have one |
| profundus | deep |
| foot and toe extensors | tibalis anterior |
| actin | forms a cross-bride with myosin which shortens the sarcomere |
| abdominal wall | rectus abdominis, external oblique, internal oblique, transverse abdominis, and line alba |
| oblique | diagonal |
| insertion | opposite end of the origin, crosses at least one joint from the origin |
| antagonist | the muscle that does the opposite of the prime mover |
| transverse | sideways/across |
| receptors | ACh attaches to this in the sarcolemma |
| gluteus | buttock |
| pectoralis | chest |
| axon terminal | enlarged end of the motor neuron and contains sacs of neurotransmitter acetylcholine |
| cleido | clavicle |
| rhomboid | diamond shaped |
| glutes | gluetus maximus, gluteus medius, and gluteus minimus |
| sterno | sternum |
| myofilaments | fine protein fibers that make up a myofibril |
| triceps | 3 heads |
| troponin and tropomyosin | inhibitory proteins that prevent contraction when relaxed |
| thermogenesis | is due to friction and chemical reactions, increased with increased activity |
| deltoid | triangular |
| tropomyosin and troponin | attach to actin and block myosin from forming a cross bridge |
| extensor | extends |
| fascicles | bundles of muscle fiber |
| levator | elevates |
| sarcolemma | special name for the cell membrane of the muscle cell |
| lateralis | lateral |
| endomysium | delicate connective tissue covering each muscle fiber |
| brevis | short |
| functions of muscular system | provides mobility, provides movement, and produces heat |
| tendons | made of dense fibrous connective tissue and a continuation of deep fascia |
| acetylcholine | chemical messenger released from the end of a motor neuron |
| cholinesterase | deactivates ACh |
| hamstrings | biceps femoris, semitendinosus, and semimembranosus |
| digiti | fingers or toes |
| quadriceps femoris | rectus femoris, vastus lateralis, vastus intermedius, and vastus medialis |
| quadriceps | 4 heads |
| radialis | radius bone |
| insertion | determines what the action of the muscle is |
| trapezius | trapezoidal |
| head and neck | frontalis, orbicularis oculi, masseter, temporalis, sternocleidomastoid and orbicularis oris |
| tendons | merge with the periosteum to anchor to bone |
