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Anatomy/Muscles
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 |