Flashcards in L11: Skeletal Muscle Organ, Structure and Function Deck (57):
what are the three types of muscles?
what makes up skeletal muscle tissue?
- muscle cells
- extracellular matrix (minimal)
muscle cell/fibre are/consist of?
what are myofibrils?
- bundles of myofilaments
what are myofilaments?
- actin and myosin contractile proteins
classification of type 1 skeletal muscle cells
- slow oxidative
- slow aerobic
size of type 1 skeletal muscle cells
function and power of type 1 skeletal muscle cells
- fatigue resistant
- least powerful
classification of type 2a skeletal muscle cells
- fast oxidative
- fast aerobic
size of type 2a skeletal muscle cells
fatigue resistance of type 2a skeletal muscle cells?
- some fatigue resistance
classification of type 2b skeletal muscle cells
- fast glycolytic
- fast anaerobic
size of type 2b skeletal muscle cells
Properties of type 2b skeletal muscle cells
- most powerful
- most common
each muscle contains a combination of the fibre types
TRUE or FALSE?
- %s vary according to function
how many tissues present in skeletal muscle organs?
- 4 tissues
what is a myotendinous junction?
- collagen fibrils of the tendon attach to the end of the muscle fibres
what is ethesis?
- where a tendon or ligament attaches to bone
what do collagen fibrils attach to?
- periosteum and/or anchor into the bone tissue
what is a motor unit?
a single motor neuron and the muscle fibres it innervates
what is an isometric contraction?
- muscle force matches load
- constant length
what are isotonic contractions?
what is a concentric contraction?
- muscle force >load
- muscle shortens
-e.g lifting weight
- muscle force
what is isokinetic?
what are sphincters
- fibres arranged concentrically around an opening
example of sphincters?
- orbicularis oris
- orbicularis oculi
what is parallel muscle architecture
- fascicles parallel to muscle
example of fascicles parallel to muscle
- biceps brachii
- rectus abdominis
what is convergent muscle architecture?
- fibres converge toward a common attachment site
example of convergent muscles?
- pectoralis major
- latissimus dorsi
what is pennate (feather) muscle architecture?
- fascicles at an oblique angle to the tendon
what are the three different types of pennate muscles
the extensor digitorum is what sort of pennate muscle?
the arrangement of fascicles in the rectus femoris is?
the arrangement of fascicles in the deltoid is ?
function of parallel muscles
function of pennate muscles
function of axial muscles
- stabilise or move elements of axial body
function of appendicular muscles
- stabilise or move appendicular body
3 compartments of the thigh?
3 compartments of the leg?
what must a muscle cross in order to actively move a joint
- cross a joint
what determines which movements are available?
joint structural and functional classification
what helps predict a muscles general action relative to the joint it crosses
- the location of a muscle
the amount of force that a muscle produces is a function of its?
physiological cross sectional area (PCSA)
what is line of action?
when a muscle contracts concentrically it will pull its attachment site toward the centre of the muscle belly
for a given force, the resultant moment will be affected by its?
- moment arm
in biomechanics, bones are considered
in biomechanics, joints are considered
axes/ centre of rotation (COR)
in biomechanics, muscles provide ?
force = pull
what is moment of force?
- strength of rotation of body segment
-produced by force
what is moment arm?
- perpendicular distance from the COR to the line of action of the force
a force directed through the centre of rotation will produce a?
a force applied at a distance from the centre of rotation will produce a??
rotation called moment of force
when a force acts on an object, and the object is fixed at some point, the object will?
- rotate around the fixed point
- results in a rotation called moment of force