Muscular system part 2 Flashcards
Incomplete - Some relaxation occurs between
contractions
The results are summed
Unfused tetanus
One contraction is immediately
followed by another
Tetanus
No evidence of relaxation before
the following contractions
The result is a sustained muscle
contraction
Fused (complete) tetanus
CP supplies are exhausted in
Less than 15 sec
Glucose is broken down to carbon dioxide
and water, releasing energy (ATP)
This is a slower reaction that requires
continuous oxygen
A series of metabolic pathways occur in
the mitochondria
Aerobic respiration
Common cause for muscle fatigue is
Oxygen dept
Myofilaments are able to slide past each
other during contractions
The muscle shortens and movement
occurs
Isotonic contractions
Tension in the muscles increases
The muscle is unable to shorten or
produce movement
Isometric contractions
Loss of tone/paralysis
Caused by nerve damage; muscle is no longer
stimulated
Results in flaccid (soft/flabby) muscle
Atrophy will begin (waste away)
Homeostatic imbalance:
Attachment to a moveable bone
Origin
Attachment to an immovable bone
Insertion
Decreases the angle of the joint
Brings two bones closer together
Typical of hinge joints like knee and elbow
Flexion
Opposite of flexion
Increases angle between two bones
Extension
Movement of a bone around its longitudinal
axis
Common in ball-and-socket joints
Example is when you move atlas around the
dens of axis (shake your head “no”)
Rotation
Movement of a limb away from the midline
Abduction
Opposite of abduction
Movement of a limb toward the midline
Adduction
Combination of flexion, extension,
abduction, and adduction
Common in ball-and-socket joints
Circumduction
Lifting the foot so that the superior surface
approaches the shin
Plantar flexion
Depressing the foot (pointing the toes)
Turn sole of foot medially
Inversion
Turn sole of foot laterally
Eversion
Forearm rotates medially so palm faces
posteriorly
Pronation
Forearm rotates laterally so palm faces
anteriorly
Supination
muscle with the major
responsibility for a certain movement
Prime mover
muscle that opposes or reverses a
prime mover
Antagonist
Move thumb to touch the tips of
other fingers on the same hand
Opposition
muscle that aids a prime mover in a
movement and helps prevent rotation
Synergist
pulls the corners of the mouth
inferiorly
Platysma
Frontalis—raises eyebrows
Orbicularis oculi—closes eyes, squints, blinks, winks
Orbicularis oris—closes mouth and protrudes the lips
Buccinator—flattens the cheek, chews
Zygomaticus—raises corners of the mouth
Facial muscles
Masseter—closes the jaw and elevates mandible
Temporalis—synergist of the masseter, closes jaw
Chewing muscles
stabilizes the origin of a prime mover
Fixator
flexes the neck, rotates the
head
Sternocleidomastoid
injury of one of a baby’s
sternocleidomatoid muscles during difficult
birth; may result in spasms
torticollis (wryneck)
