Chapter 9 Muscular System

insertion skeletal muscle

end of a muscle is normally attached to the muscle or structure that will be moved when the muscle contracts

bipennate muscle

fascicles angle out from both sides

pennate muscle

fascicles are attached to a tendon at an angle similar in appearance to a feather

unipennate muscle

fascicles feather out at an angle from only one side of the tendon

fixator or stabilizer muscle

holds a bone in place to steady it and prevents unwanted movement during a contraction

arrangement, location and function of "epimysium"

"all" of the fascicles that make up an individual muscle are surrounded by connective tissue

arrangement, location and function of "perimysium"

"each" fascicle is surrounded by connective tissue

arrangement, location and function of "muscle fiber"

10-100 muscle fibers makeup a fascicle

innervation skeletal muscle

Involuntary muscles are innervated by the autonomic nervous system; voluntary. muscles by the peripheral. In skeletal muscle the point of innervation is called the motor point. The motor unit consists of a motor nerve fiber and all the muscle fibers it innervates.

2 examples of unipennate muscle

Palmar interosseous and semimembranous (lower arm and upper leg)

2 examples of convergent muscle

Pectoralis major and temporalis

example of bipennate

Rectus femoris

What is a muscle fiber

a muscle cell

what is a aponeurosis

a sheet of pearly-white fibrous tissue that takes the place of a tendon in sheetlike muscles having a wide area of attachment.

example of fusiform muscle

biceps brachii

convergent muscle

broad muscle with fascicles that taper into a single tendon

what category of muscle often functions as a sphincter

circular muscles

what is a tendon

connective tissue that connects the muscle to a bone

example multipennate

deltoid (shoulder muscle)

parallel muscle

long evenly spaced parallel fascicles

arrangement, location and function of "fascicle"

muscle fibers are bundled together into a structure, usually 10-100 fibers make up a fascicle

circular muscle

muscle is usually composed of several areas of fascicles angle away from connective tissue and giving the appearance of several feathers joined together at a single point (around eye - Orbicularis)

multipennate muscle

muscle is usually composed of several areas where fascicles angle away from connective tissue and giving the appearance of several feathers joined together at a single point

synergist muscle

muscle which works with and aids the agonist, causes the same movement as the agonist, but doesn't produce as much force

origin of skeletal muscle

normally the less moveable point - ie the muscle at the relatively stationary end of the muscle during a contraction

antagonist muscle

opposes or slows the agonist - causes the opposite action of the prime mover, usually located on the opposite side of the agonist(prime mover)

example circular muscle

orbicularis occuli and orbicularis oris (eye and mouth)

2 examples of parallel muscle

rectus abdominus, Sartorius (near thigh)

arrangement, location and function of "endomysium"

surrounds each muscle cell/fiber

arrangement, location and function of "tendon"

the fibrous connective tissues of a muscle taper down and connect to a tendon which will connect the muscle to a bone

agonist (prime mover) muscle

the muscle that produces the most force required for a given movement

action skeletal muscle

the origin and insertion affect the action

fusiform

thick middle and tapered at each end into a tendon

what are 3 categories of pennate muscle

unipennate, bipennate, multipennate