Chapter 4: The Muscles Flashcards
Structure of Skeletal Muscles
Origin
the end of a muscle which is attached to the less movable or fixed joint. The point of muscle attatchment that moves the least.
Structure of Skeletal Muscle
Insertion
the end of the muscle which is attached to the more movable bone
Structure of Skeletal Muscles
Body
“belly” the main, fleshy portion of the muscle
Structure of Skeletal Muscles
Proximal End
the orgin of a muscle
Structure of Skeletal Muscles
Distal End
the insertion
Muscle Actions
Abduction
moving a body part away from the midplane of the body
Muscle Actions
Adduction
moving a body part towards the midplane of the body
Muscle Actions
Flexion
bending a body part/increasing angle between 2 bones.
Flexors
Muscle Actions
Extension
to straighten out a body part
Extensors
Muscle Actions
Pronation
movement of the palm of the hand from forward/upward facing position to backward/downward facing position
Muscle Actions
Supination
movement of palm of hands from backward/downward position to forward/upward position
Muscle Action
Elevation
lifting a body part up
Elevators
Muscle Action
Depression
downward movement/lowering of a body part
Depressors
Muscle Actions
Rotation
movement of a bone around its longitudinal axis
Muscle Actions
Constriction
Squeezing closed
Muscle Actions
Dialation
opening/widening
Muscle Actions
Circumduction
turning or swinging a body part in a circular fashion
Muscle Actions
Protraction
forward movement
Muscle Actions
Retraction
backwards movement
Muscle Actions
Eversion
outward movement of the sole of the foot
Muscle Actions
Inversion
inward movement of the sole of the foot
Types of Muscles
Skeletal
voluntary muscles, striated, attatched to skeleton
Types of Muscles
Smooth
non-striated, involuntary, found in various organs which work automatically
Types of Muscles
Cardiac
found in heart, has striations, involuntary