Term Test 2 Flashcards
Acromion
flattened bony process that extends laterally from the scapular spine to form the bony tip of the
shoulder
Agonist
(also, prime mover) muscle whose contraction is responsible for producing a particular motion
Antagonist
muscle that opposes the action of an agonist
Ball-and-Socket Joint
synovial joint formed between the spherical end of one bone (the ball) that fits into the
depression of a second bone (the socket); found at the hip and shoulder joints; functionally
classified as a multiaxial joint
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
Condyloid Joint
synovial joint in which the shallow depression at the end of one bone receives a rounded end
from a second bone or a rounded structure formed by two bones; found at the
metacarpophalangeal joints of the fingers or the radiocarpal joint of the wrist; functionally
classified as a biaxial joint
Contractility
ability to shorten (contract) forcibly
Contraction Phase
twitch contraction phase when tension increases action potential
Coracoid Process
short, hook-like process that projects anteriorly and laterally from the superior margin of the
scapula
Costal Cartilage
hyaline cartilage structure attached to the anterior end of each rib that provides for either direct
or indirect attachment of most ribs to the sternum
Deltoid
shoulder muscle that abducts the arm as well as flexes and medially rotates it, and extends
and laterally rotates it
Deltoid Tuberosity
roughened, V-shaped region located laterally on the mid-shaft of the humerus
extensor
Extensor Carpi Ulnarius
muscle that extends and adducts the hand
Fixator
synergist that assists an agonist by preventing or reducing movement at another joint, thereby
stabilizing the origin of the agonist
Flexor Carpi Ulnaris
muscle that flexes and adducts the hand at the wrist
Glenohumeral Joint
shoulder joint; formed by the articulation between the glenoid cavity of the scapula and the
head of the humerus
Glenoid Cavity
(also, glenoid fossa) shallow depression located on the lateral scapula, between the superior
and lateral borders
Hamate
from the lateral side, the fourth of the four distal carpal bones
Head of the Humerus
smooth, rounded region on the medial side of the proximal humerus; articulates with the
glenoid fossa of the scapula to form the glenohumeral (shoulder) joint
Hinge Joint
synovial joint at which the convex surface of one bone articulates with the concave surface of a
second bone; includes the elbow, knee, ankle, and interphalangeal joints; functionally classified
as a uniaxial joint
Hook of the Hamate Bone
bony extension located on the anterior side of the hamate carpal bone
Iliac Crest
curved, superior margin of the ilium
Infraglenoid Tubercle
small bump or roughened area located on the lateral border of the scapula, near the inferior
margin of the glenoid cavity
Intertubercular Groove (sulcus)
bicipital groove; narrow groove located between the greater and lesser tubercles of the
humerus
Latent Period
the time when a twitch does not produce contraction
Lateral Epicondyle of the Humerus
small projection located on the lateral side of the distal humerus
Latissimus Dorsi
broad, triangular axial muscle located on the inferior part of the back
Medial Border of the Scapula
elongated, medial margin of the scapula
Medial Epicondyle of the Humerus
enlarged projection located on the medial side of the distal humerus
Motor Unit
motor neuron and the group of muscle fibers it innervates
Muscle Tension
force generated by the contraction of the muscle; tension generated during isotonic
contractions and isometric contractions
Muscle Tone
low levels of muscle contraction that occur when a muscle is not producing movement
Myogram
instrument used to measure twitch tension
Olecranon Process
expanded posterior and superior portions of the proximal ulna; forms the bony tip of the elbow
Opponens Digiti (minimi)
muscle that brings the little finger across the palm to meet the thumb
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
Prime Mover (aka agonist)
principle muscle involved in an action
Pronator Teres
pronator that originates on the humerus and inserts on the radius
Recruitment
increase in the number of motor units involved in contraction
Relaxation Phase
period after twitch contraction when tension decreases
Rhomboid Major
muscle that attaches the vertebral border of the scapula to the spinous process of the thoracic
vertebrae
Spine of the Scapula
prominent ridge passing mediolaterally across the upper portion of the posterior scapular
surface
Supinator
muscle that moves the palm and forearm anteriorly
Supraglenoid Tubercle
small bump located at the superior margin of the glenoid cavity
Synergist
muscle whose contraction helps a prime mover in an action
Tetanus
a continuous fused contraction
Trapezius
muscle that stabilizes the upper part of the back
Tri
Three
Triceps Brachii
three-headed muscle that extends the forearm
Twitch
single contraction produced by one action potential
Wave Summation
addition of successive neural stimuli to produce greater contraction
change in voltage of a cell membrane in response to a stimulus that results in transmission of
an electrical signal; unique to neurons and muscle fibers
Activation Gate
part of the voltage-gated Na+ channel that opens when the membrane voltage reaches
threshold
Axon
single process of the neuron that carries an electrical signal (action potential) away from the
cell body toward a target cell
Axon Hillock
tapering of the neuron cell body that gives rise to the axon
Axon Segment
single stretch of the axon insulated by myelin and bounded by nodes of Ranvier at either end
(except for the first, which is after the initial segment, and the last, which is followed by the
axon terminal)
Axon Terminal
end of the axon, where there are usually several branches extending toward the target cell
Axoplasm
cytoplasm of an axon, which is different in composition than the cytoplasm of the neuronal cell
body
Dendrite
one of many branchlike processes that extends from the neuron cell body and functions as a
contact for incoming signals (synapses) from other neurons or sensory cells
Depolarization
change in a cell membrane potential from rest toward zero
External Oblique
superficial abdominal muscle with fascicles that extend inferiorly and medially
flattened bony process that extends laterally from the scapular spine to form the bony tip of the
shoulder
Facial Nerve
cranial nerve VII (seven) extending from brain stem area to the facial muscles through
stylomastoid foramen
Foramen Ovale of the Middle Cranial Fossa
oval-shaped opening in the floor of the middle cranial fossa
Hyperpolarization
while the K+ channels are open, membrane goes slightly over the resting potential
Inactivation Gate
part of a voltage-gated Na+ channel that closes when the membrane potential reaches +30 mV
insertion
Insertion
end of a skeletal muscle that is attached to the structure (usually a bone) that is moved when
the muscle contracts
Internal Oblique
flat, intermediate abdominal muscle with fascicles that run perpendicular to those of the
external oblique
Jugular Foramen
irregularly shaped opening located in the lateral floor of the posterior cranial cavity
Lateral Pterygoid
muscle that moves the mandible from side to side
Linea Alba
white, fibrous band that runs along the midline of the trunk
Masseter
main muscle for chewing that elevates the mandible to close the mouth
Mastication
Chewing
Mastoid Process
large bony prominence on the inferior, lateral skull, just behind the earlobe
Membrane Potential
distribution of charge across the cell membrane, based on the charges of ions
Nerve
cord-like bundle of axons located in the peripheral nervous system that transmits sensory input
and response output to and from the central nervous system
Neuron
neural tissue cell that is primarily responsible for generating and propagating electrical signals
into, within, and out of the nervous system
Oblique
At an angle
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
Rectus Abdominis
long, linear muscle that extends along the middle of the trunk
Refractory Period
time after the initiation of an action potential when another action potential cannot be
generated
Repolarization
return of the membrane potential to its normally negative voltage at the end of the action
potential
Resting Membrane Potential
the difference in voltage measured across a cell membrane under steady-state conditions,
typically -70 mV
Phrenic Nerve
nerve is connected to the spinal cord at cervical levels 3 to 5 responsible for the muscle
contractions that drive ventilation
Spinal Cord
organ of the central nervous system found within the vertebral cavity and connected with the
periphery through spinal nerves; mediates reflex behaviors
Splenius Capitis
neck muscle that inserts into the head region
Sternocleidomastoid
major muscle that laterally flexes and rotates the head
Stylomastoid Foramen
opening located on inferior skull, between the styloid process and mastoid process
styloid
Styloid Process
downward projecting, elongated bony process located on the inferior aspect of the skull
Synapse
narrow junction across which a chemical signal passes from neuron to the next, initiating a new
electrical signal in the target cell
Synaptic Cleft
small gap between cells in a chemical synapse where neurotransmitter diffuses from the
presynaptic element to the postsynaptic element
Temporalis
muscle that retracts the mandible
Threshold
membrane voltage at which an action potential is initiated
Transversus Abdominus
muscle that compresses abdominal viscera
Trigeminal Nerve
cranial nerve V (five) extending from brain stem area to the jaw muscles through foramen ovale
Voltage-Gated Channel
ion channel that opens because of a change in the charge distributed across the membrane
where it is located
Zygomaticus Major
muscle that draws upper lip upwards
