Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Ch. 6 Muscles
| Question | Answer |
|---|---|
| Contractility | ability of skeletal muscle to shorten with force |
| Excitability | capacity of skeletal muscle to respond to a stimulus |
| Elasticity | ability to recoil to original resting length after been stretched |
| Epimysium | connective tissue sheath surrounded by each skeletal muscle |
| Fascia | connective tissue located outside the epimysium; surrounds and separates the muscles |
| Perimysium | loose connective sheath that surrounds muscle fasciculi |
| endomysium | connective tissue sheath that surrounds each fiber |
| myofibrils | threadlike structure that extends from one end of the fiber to the other |
| Actin myofilaments | thin and resemble 2 minute strands of pearls twisted together |
| myosin myofilaments | thick and resemble bundles of minute golf clubs |
| Sarcomere | highly ordered units formed from actin and myosin. Extends from one Z line to another Z line |
| resting membrane potential | charge difference across the membrane |
| action potential | brief reversal back of the charge |
| motor neurons | nerve cells that carry action potentials to skeletal muscle fibers |
| neuromuscular junction | also called a synapse and forms when each branch connects to the muscle |
| motor unit | single motor neuron and all the skeletal muscle fibers it innervates |
| presynaptic terminal | the enlarged nerve terminal |
| synaptic cleft | space between the presynaptic terminal and the muscle cell |
| postsynaptic terminal | the muscle fiber |
| synaptic vesicles | located in the presynaptic terminal and secrete a neurotransmitter |
| acetylcholine | neurotransmitter and it diffuses across the synaptic cleft and binds to the postsynaptic terminal |
| exocytosis | process when an action potential reaches the nerve terminal, it causes the synaptic vesicles to release acetylcholine into the synaptic cleft |
| acetylcholinesterase | enzymatic breakdown that happens when acetylcholine is released into the synaptic cleft between the neuron and muscle cell |
| sliding filament mechanism | sliding of actin past myosin during contraction |
| muscle twitch | contraction of an entire muscle in response to a stimulus |
| threshold | a level the stimulus has to reach in order for the muscle fiber to respond to the stimulus |
| lag phase | time between application of a stimulus to a motor neuron and the beginning of a contraction |
| contraction phase | the time of contraction |
| relaxation phase | time during which the muscle relaxes |
| tetany | when the muscle remains contracted without relaxing |
| recruitment | increase in number of motor units being activated |
| anaerobic respiration | without oxygen |
| aerobic respiration | with oxygen |
| oxygen debt | amount of oxygen needed in chemical reactions to convert lactic acid to glucose and to replenish the stored creatine phosphate stored in muscle cells |
| muscle fatigue | results when ATP is used during muscle contraction faster than it can be produced in muscle cells |
| isometric | length of the muscle does not change but the amount of tension increases during contraction |
| isotonic | amount of tension produced by the muscle is constant during contraction but the length of the muscle changes |
| muscle tone | refers to constant tension produced by muscles of the body for long periods of time |
| fast-twitch fibers | contract and fatigue quickly |
| slow-twitch fibers | contract more slowly and are more resistant to fatigue |
| origin | the most stationary end of the muscle |
| insertion | end of the muscle undergoing the greatest movement |
| belly | portion of muscle between the origin and the insertion |
| synergists | muscles that work together to accomplish specific movements |
| antagonist | muscles that work together in opposition to one another |
| prime mover | among group of synergists, one muscle plays the major role in accomplishing the desired movement |
| occipitofrontalis | raises the eyebrows |
| orbicularis oculi | closes the eyelids and causes crows feet wrinkles in the skin at the lateral corners of the eye |
| orbicularis oris | puckers the lips |
| buccinator | flattens the cheeks |
| zygomaticus | smiling muscle |
| levator labii superioris | sneering |
| depressor anguli oris | frowning |
| mastication | chewing |
| intrinsic tongue muscles | changes the shape of the tongue |
| extrinsic tongue muscles | moves the tongue |
| sternocleidomastiod | lateral neck muscle and prime mover; rotates and abducts the head |
| platysma | sheetlike muscle that covers the anterolateral neck |
| erector spinae | Group of muscles on each side of the back; responsible for keeping the back straight and the body erect |
| thoracic muscles | muscles that move the thorax |
| external intercostals | elevate the ribs during inspiration |
| internal intercostals | contract during forced expiration |
| linea alba | tendinous area of the abdominal wall that extends from the sternum through the navel to the pubis |
| trapezius | rotates the scapula |
| serratus anterior | pulls scapula anteriorly |
| pectoralis major | abducts and flexes the arm |
| latissimus dorsi | medially rotates, adducts, and powerfully extends the arm |
| deltoid | attaches the humerus to the scapula and the clavicle and is the major abductor of the upper limb |
| triceps brachii | extends the forearm |
| biceps brachii | flexes the forearm |
| brachialis | flexes forearm |
| brachioradialis | flexes and supinates the forearm |
| flexor carpi | flexes the wrist |
| Extensor carpi | extends the wrist |
| flexor digitorum | flexes the fingers |
Created by:
Tessa22
Popular Anatomy sets