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45 terms

Unit 4 Key Terms

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abduction
movement away from the midline of the body
adduction
movement toward the midline of the body
articular cartilage
hyaline cartilage attached to articular bone surfaces
articulation
the action or manner in which the parts come together at a joint
ball-and-socket joint
an articulation in which the rounded head of one bone fits into a cuplike cavity of the other and admits movement in any direction
cartilage
a usually translucent somewhat elastic tissue that composes most of the skeleton of vertebrate embryos and except for a small number of structures is replaced by bone during ossification in the higher vertebrates
circumduction
a movement at a synovial joint in which the distal end of the bone moves in a circle while the proximal end remains relatively stable
dorsiflexion
bending the foot in the direction of the dorsum (upper surface)
extension
an unbending movement around a joint in a limb that increases the angle between the bones of the limb at the joint
flexion
an unbending movement around a joint in a limb that decreases the angle between the bones of the limb at the joint
goniometer
an instrument for measuring angles (as of a joint or the skull)
hinge joint
joint between bones that permits motion in only one plane
hyaline cartilage
translucent bluish white cartilage consisting of cells embedded in an apparently homogenous matrix, present in joints and respiratory passages, and forming most of the fetal skeleton
joint
the point of contact between elements of an animal skeleton whether moveable or rigidly fixed together with the surrounding and supporting parts
ligament
dense regular connective tissue that attaches bone to bone
plantar flexion
bending the foot in the direction of the plantar surface (sole)
range of motion
the range through which a joint can be moved
rotation
moving a bone around its own axis, with no other movement
synovial cavity
the space between the articulating bones of a synovial joint, filled with synovial fluid
synovial fluid
secretion of synovial membrances that lubricates joints and nourishes articular cartilage
synovial joint
a fully moveable joint in which the synovial cavity is present between two articulating bones
tendon
a white fibrous cord of dense regular connective tissue that attaches muscle to bone
actin
a contractile protein that is part of the thin filaments in muscle fibers
cardiac muscle
striated muscle fibers that form the wall of the heart; stimulated by the intrinsic conduction system and autonomic motor neurons
carpal tunnel syndrome
a condition caused by compression of the median nerve in the carpal tunnel and characterized especially by weakness, pain, and disturbances of sensation in the hand and fingers
contract
to shorten and thicken
endomysium
the delicate connective tissue surrounding the individual muscular fibers within the smallest bundles
epimysium
the external connective sheath of a muscle
fascicle
a small bundle or cluster, especially of nerve or muscle fibers
insertion
the attachment of a muscle tendon to a moveable bone
muscle
an organ composed of one of the three types of muscular tissue, specialized for contraction to produce voluntary and involuntary movements of parts of the body
myofibril
a threadlike structure, extending longitudinally through a muscle fiber consisting mainly of thick filaments and thin filaments
myosin
the contractile protein that makes up the thick filaments of muscle fibers
nerve
a cordlike bundle of neuronal axons and/or dendrites and associated connective tissue coursing together outside the central nervous system
origin
the attachment of a muscle tendon to a stationary bone
perimysium
the connective-tissue sheath that surrounds a muscle and forms sheaths for the bundles of muscle fibers
plexus
network of interlacing blood vessels or nerves
rigor mortis
temporary rigidity of muscles occurring after death
sarcomere
any of the repeating structural units of striated muscle fibrils
skeletal muscle
an organ specialized for contraction, composed of striated muscle fibers, supported by connective tissue, attached to bone by a tendon or aponeurosis, and stimulated by comatic motor neurons
sliding filament mechanism
the explanation of how thick and thin filaments slide relative to one another during striated muscle contraction to decrease sarcomere length
smooth muscle
a tissue specialized for contraction, composed of smooth muscle fibers, located in the walls of hollow internal organs, and innervated by the autonomic motor neurons
striation
any of the alternate dark and light cross bands of a myofibril of striated muscle
tropomyosin
a protein of muscle that forms a complex with troponin regulating the interaction of actin and myosin in muscular contraction
troponin
a protein of muscle that together with tropomyosin forms a regulatory protein complex controlling the interaction of actin and myosin and that, when combined with calcium ions, permits muscular contraction