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Muscles
Question | Answer |
---|---|
contractility | shorten with force |
excitability | respond to a stimulus |
extensibility | ability to be stretched |
elasticity | recoil to their original resting length after they have been stretched |
epimysium | skeletal muscle surrounded by a connective tissue sheath |
fascia | another connective located outside the epimysium |
fascicle | muscle composed of numerous visible bundles |
perimysium | surrounded by loose connective tissue |
fibers | single muscle cells |
muscle fiber | single cylindrical cell containing several nuclei |
endomysium | connective tissue sheath |
myofibrils | threadlike structure |
2 major kinds of protein fiber | actin - thin myosin - thick |
actin and myosin form | sarcomeres |
muscle twitch | contraction of an entire muscle |
isometric | equal distance (holding ball) |
isotonic | equal tension (throwing ball) |
fast-twitch fibers | contract quickly and fatigue quickly (white meat of a chicken breast) |
slow-twitch fibers | contract slowly (dark meat of a duck's breast or the legs of a chicken) |
origin (head) | most stationary end of a muscle |
insertion | end of muscle undergoing the greatest movement |
belly | muscle between the origin and the insertion |
synergists | work together to accomplish specific movments |
antagonists | muscle that work in oppostion to one another |
occipitofrontalis | raises the eyebrows |
oribicularis oculi | closes eyelid (crow feet) |
kissing muscles | orbicularis oris and buccinator |
puckers the lips | orbicularis oris |
flattens the cheeks | buccinator |
zygomaticus | smiling muscle |
levator labii superoris | sneering |
depressor anguli oris | frowning |
two mastication muscles | temporalis and masseter |
mastication | chewing |
sternocleidomastoid | rotates and extends the neck |
intrinsic | changes shape of tongue |
extrinsic | moves the tongue |
external intercostals | elevate the ribs during inspiration |
internal intercostals | contract during forced expiration |
diaphragm | accomplishes quiet breathing |
linea alba | tendinous area of the abdominal wall |
tendinous inscriptions | cross the rectus abdominis at three or more location |
trapezius | rotates scapula |
serratus anterior | pulls scapula anteriorly |
pectoralis major | adducts and flexes the arm |
latissimus dorsi | medially rotates, adducts, and powerfully extends arm |
deltoid | attaches the humerus to the scapula and clavicle |
triceps brachii | extends the forearm |
biceps brachii | flexes the forearm |
brachioradialis | flexes and supinates the forearm |
retinaculum (bracelet) | strong band of fibrous connective tissue |
flexor carpi | flexes the wrist |
extensor carpi | extends the wrist |
flexor digitorum | flexes the fingers |
extensor digitorum | extends the fingers |
intrinsic hand muscles | 19 hand muscles |
interossi | muscles, located between the metacarpals |
gluteus maximus | buttocks |
gluteus medius | hip muscle and common injection site |
quadriceps femoris | extends the leg; anterior thigh muscles |
sartorius | "tailors muscle" flexes the thigh |
hamstring | posterior thigh muscles; flexes the leg and extends the thigh |
gastrocnemius and soleus | forms the calf muscle |
calcaneal tendons | flex the foot and toes |
peroneus | turning the lateral side of the foot outwards |
intrinsic foot | 20 muscles located within the foot |
thoracic muscles | muscles that move the thorax |
erector spinae | group of muscles on each side of the back |
ATP (adenosine triphosphate) | needed for energy for muscle contraction |
recruitment | the increase in number of motor units being activated |
tetany | where the muscle remains contracted without relaxing |
2 types of muscle contactions | isometric and isotonic |
anaerobic respiration | without oxygen |
aerobic respiration | with oxygen |
prime mover | a group of synergists |