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Key Terms Chapter 11: The Muscular System

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    62662
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    abduct
    move away from midline in the sagittal plane
    abductor
    moves the bone away from the midline
    abductor digiti minimi
    muscle that abducts the little finger
    abductor pollicis brevis
    muscle that abducts the thumb
    abductor pollicis longus
    muscle that inserts into the first metacarpal
    adductor
    moves the bone toward the midline
    adductor brevis
    muscle that adducts and medially rotates the thigh
    adductor longus
    muscle that adducts, medially rotates, and flexes the thigh
    adductor magnus
    muscle with an anterior fascicle that adducts, medially rotates and flexes the thigh, and a posterior fascicle that assists in thigh extension
    adductor pollicis
    muscle that adducts the thumb
    agonist
    (also, prime mover) muscle whose contraction is responsible for producing a particular motion
    anal triangle
    posterior triangle of the perineum that includes the anus
    anconeus
    small muscle on the lateral posterior elbow that extends the forearm
    antagonist
    muscle that opposes the action of an agonist
    anterior compartment of the arm
    (anterior flexor compartment of the arm) the biceps brachii, brachialis, brachioradialis, and their associated blood vessels and nerves
    anterior compartment of the forearm
    (anterior flexor compartment of the forearm) deep and superficial muscles that originate on the humerus and insert into the hand
    anterior compartment of the leg
    region that includes muscles that dorsiflex the foot
    anterior compartment of the thigh
    region that includes muscles that flex the thigh and extend the leg
    anterior scalene
    a muscle anterior to the middle scalene
    appendicular
    of the arms and legs
    axial
    of the trunk and head
    belly
    bulky central body of a muscle
    bi
    two
    biceps brachii
    two-headed muscle that crosses the shoulder and elbow joints to flex the forearm while assisting in supinating it and flexing the arm at the shoulder
    biceps femoris
    hamstring muscle
    bipennate
    pennate muscle that has fascicles that are located on both sides of the tendon
    brachialis
    muscle deep to the biceps brachii that provides power in flexing the forearm.
    brachioradialis
    muscle that can flex the forearm quickly or help lift a load slowly
    brevis
    short
    buccinator
    muscle that compresses the cheek
    calcaneal tendon
    (also, Achilles tendon) strong tendon that inserts into the calcaneal bone of the ankle
    caval opening
    opening in the diaphragm that allows the inferior vena cava to pass through; foramen for the vena cava
    circular
    (also, sphincter) fascicles that are concentrically arranged around an opening
    compressor urethrae
    deep perineal muscle in women
    convergent
    fascicles that extend over a broad area and converge on a common attachment site
    coracobrachialis
    muscle that flexes and adducts the arm
    corrugator supercilii
    prime mover of the eyebrows
    deep anterior compartment
    flexor pollicis longus, flexor digitorum profundus, and their associated blood vessels and nerves
    deep posterior compartment of the forearm
    (deep posterior extensor compartment of the forearm) the abductor pollicis longus, extensor pollicis brevis, extensor pollicis longus, extensor indicis, and their associated blood vessels and nerves
    deep transverse perineal
    deep perineal muscle in men
    deglutition
    swallowing
    deltoid
    shoulder muscle that abducts the arm as well as flexes and medially rotates it, and extends and laterally rotates it
    diaphragm
    skeletal muscle that separates the thoracic and abdominal cavities and is dome-shaped at rest
    digastric
    muscle that has anterior and posterior bellies and elevates the hyoid bone and larynx when one swallows; it also depresses the mandible
    dorsal group
    region that includes the extensor digitorum brevis
    dorsal interossei
    muscles that abduct and flex the three middle fingers at the metacarpophalangeal joints and extend them at the interphalangeal joints
    epicranial aponeurosis
    (also, galea aponeurosis) flat broad tendon that connects the frontalis and occipitalis
    erector spinae group
    large muscle mass of the back; primary extensor of the vertebral column
    extensor
    muscle that increases the angle at the joint
    extensor carpi radialis brevis
    muscle that extends and abducts the hand at the wrist
    extensor carpi ulnaris
    muscle that extends and adducts the hand
    extensor digiti minimi
    muscle that extends the little finger
    extensor digitorum
    muscle that extends the hand at the wrist and the phalanges
    extensor digitorum brevis
    muscle that extends the toes
    extensor digitorum longus
    muscle that is lateral to the tibialis anterior
    extensor hallucis longus
    muscle that is partly deep to the tibialis anterior and extensor digitorum longus
    extensor indicis
    muscle that inserts onto the tendon of the extensor digitorum of the index finger
    extensor pollicis brevis
    muscle that inserts onto the base of the proximal phalanx of the thumb
    extensor pollicis longus
    muscle that inserts onto the base of the distal phalanx of the thumb
    extensor radialis longus
    muscle that extends and abducts the hand at the wrist
    extensor retinaculum
    band of connective tissue that extends over the dorsal surface of the hand
    external intercostal
    superficial intercostal muscles that raise the rib cage
    external oblique
    superficial abdominal muscle with fascicles that extend inferiorly and medially
    extrinsic eye muscles
    originate outside the eye and insert onto the outer surface of the white of the eye, and create eyeball movement
    extrinsic muscles of the hand
    muscles that move the wrists, hands, and fingers and originate on the arm
    fascicle
    muscle fibers bundled by perimysium into a unit
    femoral triangle
    region formed at the junction between the hip and the leg and includes the pectineus, femoral nerve, femoral artery, femoral vein, and deep inguinal lymph nodes
    fibularis brevis
    (also, peroneus brevis) muscle that plantar flexes the foot at the ankle and everts it at the intertarsal joints
    fibularis longus
    (also, peroneus longus) muscle that plantar flexes the foot at the ankle and everts it at the intertarsal joints
    fibularis tertius
    small muscle that is associated with the extensor digitorum longus
    fixator
    synergist that assists an agonist by preventing or reducing movement at another joint, thereby stabilizing the origin of the agonist
    flexion
    movement that decreases the angle of a joint
    flexor
    muscle that decreases the angle at the joint
    flexor carpi radialis
    muscle that flexes and abducts the hand at the wrist
    flexor carpi ulnaris
    muscle that flexes and adducts the hand at the wrist
    flexor digiti minimi brevis
    muscle that flexes the little finger
    flexor digitorum longus
    muscle that flexes the four small toes
    flexor digitorum profundus
    muscle that flexes the phalanges of the fingers and the hand at the wrist
    flexor digitorum superficialis
    muscle that flexes the hand and the digits
    flexor hallucis longus
    muscle that flexes the big toe
    flexor pollicis brevis
    muscle that flexes the thumb
    flexor pollicis longus
    muscle that flexes the distal phalanx of the thumb
    flexor retinaculum
    band of connective tissue that extends over the palmar surface of the hand
    frontalis
    front part of the occipitofrontalis muscle
    fusiform
    muscle that has fascicles that are spindle-shaped to create large bellies
    gastrocnemius
    most superficial muscle of the calf
    genioglossus
    muscle that originates on the mandible and allows the tongue to move downward and forward
    geniohyoid
    muscle that depresses the mandible, and raises and pulls the hyoid bone anteriorly
    gluteal group
    muscle group that extends, flexes, rotates, adducts, and abducts the femur
    gluteus maximus
    largest of the gluteus muscles that extends the femur
    gluteus medius
    muscle deep to the gluteus maximus that abducts the femur at the hip
    gluteus minimus
    smallest of the gluteal muscles and deep to the gluteus medius
    gracilis
    muscle that adducts the thigh and flexes the leg at the knee
    hamstring group
    three long muscles on the back of the leg
    hyoglossus
    muscle that originates on the hyoid bone to move the tongue downward and flatten it
    hypothenar
    group of muscles on the medial aspect of the palm
    hypothenar eminence
    rounded contour of muscle at the base of the little finger
    iliacus
    muscle that, along with the psoas major, makes up the iliopsoas
    iliococcygeus
    muscle that makes up the levator ani along with the pubococcygeus
    iliocostalis cervicis
    muscle of the iliocostalis group associated with the cervical region
    iliocostalis group
    laterally placed muscles of the erector spinae
    iliocostalis lumborum
    muscle of the iliocostalis group associated with the lumbar region
    iliocostalis thoracis
    muscle of the iliocostalis group associated with the thoracic region
    iliopsoas group
    muscle group consisting of iliacus and psoas major muscles, that flexes the thigh at the hip, rotates it laterally, and flexes the trunk of the body onto the hip
    iliotibial tract
    muscle that inserts onto the tibia; made up of the gluteus maximus and connective tissues of the tensor fasciae latae
    inferior extensor retinaculum
    cruciate ligament of the ankle
    inferior gemellus
    muscle deep to the gluteus maximus on the lateral surface of the thigh that laterally rotates the femur at the hip
    infrahyoid muscles
    anterior neck muscles that are attached to, and inferior to the hyoid bone
    infraspinatus
    muscle that laterally rotates the arm
    innermost intercostal
    the deepest intercostal muscles that draw the ribs together
    insertion
    end of a skeletal muscle that is attached to the structure (usually a bone) that is moved when the muscle contracts
    intercostal muscles
    muscles that span the spaces between the ribs
    intermediate
    group of midpalmar muscles
    internal intercostal
    muscles the intermediate intercostal muscles that draw the ribs together
    internal oblique
    flat, intermediate abdominal muscle with fascicles that run perpendicular to those of the external oblique
    intrinsic muscles of the hand
    muscles that move the wrists, hands, and fingers and originate in the palm
    ischiococcygeus
    muscle that assists the levator ani and pulls the coccyx anteriorly
    lateral compartment of the leg
    region that includes the fibularis (peroneus) longus and the fibularis (peroneus) brevis and their associated blood vessels and nerves
    lateral pterygoid
    muscle that moves the mandible from side to side
    lateralis
    to the outside
    latissimus dorsi
    broad, triangular axial muscle located on the inferior part of the back
    levator ani
    pelvic muscle that resists intra-abdominal pressure and supports the pelvic viscera
    linea alba
    white, fibrous band that runs along the midline of the trunk
    longissimus capitis
    muscle of the longissimus group associated with the head region
    longissimus cervicis
    muscle of the longissimus group associated with the cervical region
    longissimus group
    intermediately placed muscles of the erector spinae
    longissimus thoracis
    muscle of the longissimus group associated with the thoracic region
    longus
    long
    lumbrical
    muscle that flexes each finger at the metacarpophalangeal joints and extend each finger at the interphalangeal joints
    masseter
    main muscle for chewing that elevates the mandible to close the mouth
    mastication
    chewing
    maximus
    largest
    medial compartment of the thigh
    a region that includes the adductor longus, adductor brevis, adductor magnus, pectineus, gracilis, and their associated blood vessels and nerves
    medial pterygoid
    muscle that moves the mandible from side to side
    medialis
    to the inside
    medius
    medium
    middle scalene
    longest scalene muscle, located between the anterior and posterior scalenes
    minimus
    smallest
    multifidus
    muscle of the lumbar region that helps extend and laterally flex the vertebral column
    multipennate
    pennate muscle that has a tendon branching within it
    mylohyoid
    muscle that lifts the hyoid bone and helps press the tongue to the top of the mouth
    oblique
    at an angle
    obturator externus
    muscle deep to the gluteus maximus on the lateral surface of the thigh that laterally rotates the femur at the hip
    obturator internus
    muscle deep to the gluteus maximus on the lateral surface of the thigh that laterally rotates the femur at the hip
    occipitalis
    posterior part of the occipitofrontalis muscle
    occipitofrontalis
    muscle that makes up the scalp with a frontal belly and an occipital belly
    omohyoid
    muscle that has superior and inferior bellies and depresses the hyoid bone
    opponens digiti minimi
    muscle that brings the little finger across the palm to meet the thumb
    opponens pollicis
    muscle that moves the thumb across the palm to meet another finger
    orbicularis oculi
    circular muscle that closes the eye
    orbicularis oris
    circular muscle that moves the lips
    origin
    end of a skeletal muscle that is attached to another structure (usually a bone) in a fixed position
    palatoglossus
    muscle that originates on the soft palate to elevate the back of the tongue
    palmar interossei
    muscles that abduct and flex each finger at the metacarpophalangeal joints and extend each finger at the interphalangeal joints
    palmaris longus
    muscle that provides weak flexion of the hand at the wrist
    parallel
    fascicles that extend in the same direction as the long axis of the muscle
    patellar ligament
    extension of the quadriceps tendon below the patella
    pectineus
    muscle that abducts and flexes the femur at the hip
    pectoral girdle
    shoulder girdle, made up of the clavicle and scapula
    pectoralis major
    thick, fan-shaped axial muscle that covers much of the superior thorax
    pectoralis minor
    muscle that moves the scapula and assists in inhalation
    pelvic diaphragm
    muscular sheet that comprises the levator ani and the ischiococcygeus
    pelvic girdle
    hips, a foundation for the lower limb
    pennate
    fascicles that are arranged differently based on their angles to the tendon
    perineum
    diamond-shaped region between the pubic symphysis, coccyx, and ischial tuberosities
    piriformis
    muscle deep to the gluteus maximus on the lateral surface of the thigh that laterally rotates the femur at the hip
    plantar aponeurosis
    muscle that supports the longitudinal arch of the foot
    plantar group
    four-layered group of intrinsic foot muscles
    plantaris
    muscle that runs obliquely between the gastrocnemius and the soleus
    popliteal fossa
    diamond-shaped space at the back of the knee
    popliteus
    muscle that flexes the leg at the knee and creates the floor of the popliteal fossa
    posterior compartment of the leg
    region that includes the superficial gastrocnemius, soleus, and plantaris, and the deep popliteus, flexor digitorum longus, flexor hallucis longus, and tibialis posterior
    posterior compartment of the thigh
    region that includes muscles that flex the leg and extend the thigh
    posterior scalene
    smallest scalene muscle, located posterior to the middle scalene
    prime mover
    (also, agonist) principle muscle involved in an action
    pronator quadratus
    pronator that originates on the ulna and inserts on the radius
    pronator teres
    pronator that originates on the humerus and inserts on the radius
    psoas major
    muscle that, along with the iliacus, makes up the iliopsoas
    pubococcygeus
    muscle that makes up the levator ani along with the iliococcygeus
    quadratus femoris
    muscle deep to the gluteus maximus on the lateral surface of the thigh that laterally rotates the femur at the hip
    quadratus lumborum
    posterior part of the abdominal wall that helps with posture and stabilization of the body
    quadriceps femoris group
    four muscles, that extend and stabilize the knee
    quadriceps tendon
    (also, patellar tendon) tendon common to all four quadriceps muscles, inserts into the patella
    rectus
    straight
    rectus abdominis
    long, linear muscle that extends along the middle of the trunk
    rectus femoris
    quadricep muscle on the anterior aspect of the thigh
    rectus sheaths
    tissue that makes up the linea alba
    retinacula
    fibrous bands that sheath the tendons at the wrist
    rhomboid major
    muscle that attaches the vertebral border of the scapula to the spinous process of the thoracic vertebrae
    rhomboid minor
    muscle that attaches the vertebral border of the scapula to the spinous process of the thoracic vertebrae
    rotator cuff
    (also, musculotendinous cuff) the circle of tendons around the shoulder joint
    sartorius
    band-like muscle that flexes, abducts, and laterally rotates the leg at the hip
    scalene muscles
    flex, laterally flex, and rotate the head; contribute to deep inhalation
    segmental muscle group
    interspinales and intertransversarii muscles that bring together the spinous and transverse processes of each consecutive vertebra
    semimembranosus
    hamstring muscle
    semispinalis capitis
    transversospinales muscle associated with the head region
    semispinalis cervicis
    transversospinales muscle associated with the cervical region
    semispinalis thoracis
    transversospinales muscle associated with the thoracic region
    semitendinosus
    hamstring muscle
    serratus anterior
    large and flat muscle that originates on the ribs and inserts onto the scapula
    soleus
    wide, flat muscle deep to the gastrocnemius
    sphincter urethrovaginalis
    deep perineal muscle in women
    spinalis capitis
    muscle of the spinalis group associated with the head region
    spinalis cervicis
    muscle of the spinalis group associated with the cervical region
    spinalis group
    medially placed muscles of the erector spinae
    spinalis thoracis
    muscle of the spinalis group associated with the thoracic region
    splenius
    posterior neck muscles; includes the splenius capitis and splenius cervicis
    splenius capitis
    neck muscle that inserts into the head region
    splenius cervicis
    neck muscle that inserts into the cervical region
    sternocleidomastoid
    major muscle that laterally flexes and rotates the head
    sternohyoid
    muscle that depresses the hyoid bone
    sternothyroid
    muscle that depresses the larynx’s thyroid cartilage
    styloglossus
    muscle that originates on the styloid bone, and allows upward and backward motion of the tongue
    stylohyoid
    muscle that elevates the hyoid bone posteriorly
    subclavius
    muscle that stabilizes the clavicle during movement
    subscapularis
    muscle that originates on the anterior scapula and medially rotates the arm
    superficial anterior compartment of the forearm
    flexor carpi radialis, palmaris longus, flexor carpi ulnaris, flexor digitorum superficialis, and their associated blood vessels and nerves
    superficial posterior compartment of the forearm
    extensor radialis longus, extensor carpi radialis brevis, extensor digitorum, extensor digiti minimi, extensor carpi ulnaris, and their associated blood vessels and nerves
    superior extensor retinaculum
    transverse ligament of the ankle
    superior gemellus
    muscle deep to the gluteus maximus on the lateral surface of the thigh that laterally rotates the femur at the hip
    supinator
    muscle that moves the palm and forearm anteriorly
    suprahyoid muscles
    neck muscles that are superior to the hyoid bone
    supraspinatus
    muscle that abducts the arm
    synergist
    muscle whose contraction helps a prime mover in an action
    temporalis
    muscle that retracts the mandible
    tendinous intersections
    three transverse bands of collagen fibers that divide the rectus abdominis into segments
    tensor fascia lata
    muscle that flexes and abducts the thigh
    teres major
    muscle that extends the arm and assists in adduction and medial rotation of it
    teres minor
    muscle that laterally rotates and extends the arm
    thenar
    group of muscles on the lateral aspect of the palm
    thenar eminence
    rounded contour of muscle at the base of the thumb
    thyrohyoid
    muscle that depresses the hyoid bone and elevates the larynx’s thyroid cartilage
    tibialis anterior
    muscle located on the lateral surface of the tibia
    tibialis posterior
    muscle that plantar flexes and inverts the foot
    transversospinales
    muscles that originate at the transverse processes and insert at the spinous processes of the vertebrae
    transversus abdominis
    deep layer of the abdomen that has fascicles arranged transversely around the abdomen
    trapezius
    muscle that stabilizes the upper part of the back
    tri
    three
    triceps brachii
    three-headed muscle that extends the forearm
    unipennate
    pennate muscle that has fascicles located on one side of the tendon
    urogenital triangle
    anterior triangle of the perineum that includes the external genitals
    vastus intermedius
    quadricep muscle that is between the vastus lateralis and vastus medialis and is deep to the rectus femoris
    vastus lateralis
    quadricep muscle on the lateral aspect of the thigh
    vastus medialis
    quadricep muscle on the medial aspect of the thigh
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