| Question | Answer |
| The ability of skeletal muscle to shorten with force? | Contractility |
| The capacity of skeletal muscle to respond to a stimulus? | Excitability |
| the ability to bw streched? | Extensibility |
| Ability to recoil to their original resting length after they have been stretched? | Elasticity |
| Each skletal muscle is surrounded by a conncetive tissue sheath called? | Epimysium |
| Another connective tissure located outside the epimysium? | Fascia |
| A muscle is composed of numerous visible bundles called? | Muscle Fasciculi (Fascicle) |
| Fasciculi (Fascicle) are surrounded by loose connective tissue called? | Perumysium |
| The fasciculi are composed of single muscle cells called? | Fibers |
| Each fiber is surrouned by a connective tissue sheath called? | Endomysium |
| The cytoplasm of each fiber is filled with? | Myofibrils |
| A threadlike structure that extends from one end of the fiber to the other? | Myofibrils |
| Myofibrils consist of 2 major kinds of protein fibers: | Actin and Myosin Myofilaments |
| Resemble 2 minute strands of pearls twisted together? | Actin |
| Resemble bundles of minute golf clubs? | Myosin |
| Actin and myosin myofilaments form highly ordered units called? | Sarcomeres |
| The basic stuctural and functional unit of the muscle? | Saromere |
| The charge difference across the membrane is called? | resting membrane potential |
| When a muscle cell is stimulated the membrane charateristics change briefly, the brief reversal back of the charge is called? | action potential |
| Nerve cells that carry action potentials to the sketetal muscle fibers? | motor neurons |
| Axons enter the muscles and branch, each branch that connects to the muscle forms? | A neuromusclular junction or synapse |
| A single motor neuron and all the skeletal muscle fibers in innervates are called? | a motor unit |
| the enlarged nerve terminal: | presynaptoc terminal |
| Space between the presynaptic terminal and the muscle cell : | synaptic cleft |
| Each presynaptic terminal contains: | synaptic vesicles |
| Synaptic vesicles secrete a neurotransmitter called? | acetylcholine |
| The acetylcholine released into the synaptic cleft between the neuron and muscle cell is rapidly broken down by an enzymes: | Acetylcholinesterase |
| Occurs as action and myosin myofilaments slide past one another causing the sarcomeres to shorten: | Muscle Contraction |
| Tje sliding of action mypfilaments past myosin myofilments during contraction is called? | Sliding Filament Mechanism |
| Contraction of an entire muscle in responce to a stimulus that causes the avtion potential in one or more muscle fibers: | Muscle Twitch |
| A muscle fiber will not respong to a stimulus unti that stimulus reaches a level called? | threshold |
| The time between app;ication of a stimulus to a motor neuron and the beginning of a contraction is? | the lag phase |
| Time of contraction: | contraction phase |
| Time during which the muscle relaxes: | relaxation phase |
| Muscle remains contracted without relaxing: | Tetany |
| The increase in number of motor units being activated is called? | recruitment |
| Needed for energy for muscle contraction: | ATP (adenosine triphosphate) |
| ATP is: | produced in the mitochondria, short-lived and unstable |
| when at rest they cant stockplie ATP but they can store another high engery molecule called? | creatine phosphate |
| Anaerobic Respiration: | without oxygen |
| Aerobic Respiration: | with oxygen |
| The amount of oxygen needed in chemical reactions to convert lactic acid to glucose and to replenish the depleted stores of creatine phosphate stores in muscle cells: | Oxygen Debt |
| Results when ATP is used during muscle contraction faster than it can be produced in the muscle cell: | muscle fatigue |
| The length of the muscle does not change, but the amount of tension increases during the contraction process: | Isometric (equal distance) |
| The amount of tension prodused by the muscle is constant during contraction, but the length of the muscle changes: | Isotonic (equal tension) |
| Constant tension produced by muscles of the body for long periods of time: | Muscle Tone |
| Contract quickly and fatigue quickly: | Fast-Twitch Fibers (white meat of a chickens breast) |
| Contract more slowly and are more resistant to fatigue: | Slow-Twitch Fibers (dark meat of a ducks breast or leg of chicken) |
| The most stationary end of the muscle: | Origin (head) |
| The end of the muscle undergoing the greatest movment: | Insertion |
| The portion of the muscle between the orgin and the insertion: | belly |
| Muscles that work together to accomplish specific movements are called? | synergists |
| Muscles that work in opposition to one another are called? | antagonists |
| Among a group of synergists, if one muscle plays the major role in accomplishing the desired movement, it is: | the prime mover |
| occipitofrontales | rasies eyebrows |
| orbicularis oculi | closes the eyelid |
| orbiccularis oris | puckers the lips |
| buccinator | flattens the cheeks |
| the two "kissing muscles" | orbicularis oris, buccinator |
| zygomatius | smiling |
| levator labii superioris | sneering |
| depressor anguli oris | frowning |
| mastication | chewing |
| 4 pairs of chewing (mastication | Masseter, Temporalis, 2 pterygoids |
| extrinsic tongue muscles | moves the tongue |
| intrinsic tongue muscles | changes shape of tongue |
| stero cleido mastoid | roatates and abducts neck |
| found in each side of the back, responable for erect posture | erector spinae |
| contract during inspiration | external intercostals |
| contract during forced expirations | internal intercostals |
| dome shaped muscle, responible for quiet breating | diaphragm |
| abs | rectus abdominis |
| white line of conn. tissue that extends from the sternum to the pelvis | linea alba |
| cross the rextus abdominis in 3 places and form a segmemted look in abs | tendinous inscription |
| muscles that move the vertebral column | truck muscles |
| muscles that move the thorax | thoracic muscles |
| muscles of the anterior abdominal wall flex and rotate the verebral column, compress the abdominal cavity, and hold in the abdominal viscera | abdominal wall muscles |
| trapezius | rotates scapula |
| pulls scapula anteriorly | serratus anterior |
| the arm is attached to the thorax by the.. | pectoralis major and latissimus dorsi muscles |
| adducts and flexes the arm | pectoralis major |
| medially rotaes, adducts, and powerfully extends the arm. "swimmers muscles" | latissimus dorsi |
| attaches the humerus to the scapula and clavicle and is the major abductor of the upper limb. | deltoid |
| extends the forearm, occupies the psoterior compartments of the arm. | triceps brachii |
| flexes the forearm, occupies the anterior compartment of the arm. | biceps brachii |
| flexes forearm | brachilalis |
| flexes and supinates forearm | brachioradialis |
| strong band of fibrous conn. tissure that conves the flexor and extensor tendons and holds them in place around the wrist so that they do not "bowstring" during muscle contraction | retinaculum (bracelet) |
| flexor carpi | flexes the wrist |
| extensor carpi | entends the wrist |
| flexor digitorum | flexs the fingers |
| extensor digitorum | extends the fingers |
| gletues maximus | buttocks |
| gluteus medius | hip muscle and common injection site |
| extends the leg, anterior thigh muscles | quadriceps fermoris |
| "tailors musscle", flexes the thigh | sartorius |
| psoterior thigh muscles: flexes the leg and extends the thigh | hamstring |
| form the claf muscles. they join together to form the calcaneal tendon. | gastrocnemius and soleus |
| calcaneal tendon (achilles tendon) | flexes the foot and toes |
| lateral muscles of the leg | peroneus |
