Unit 3 Lesson 5

Every skeletal muscle is attached to bone

false

Fascicle

group of muscle fibrils

Fixator

holds non-moving bones in place during an action

Myosin

in midde of sarcomere bracketed by actin

Smooth

involuntary, GI tract, arrector pili, blood vessels, respiratory tract

Thin filament

Actin

Perimysium

CT around fascicles

Endomysium

CT around muscle fibers

Levels of muscle membranes

Epimysium, perimysium, endomysium

Troponin

a Ca++ binding protein that is on tropomyosin

Myofilaments

actin and myosin

Z disk

actin is bound to this, marks the outer boundary of a sarcomere

Antagonist

acts opposite of the prime mover

Synergist

aids the agonist stability

Actin

attached to z-disk and brackets myosin

Flexion of the elbow synergist

biceps brachii

Origin

bone that muscles tendon attaches to that remains stationary during movement

Flexion of the elbow agonist

brachialis

Tendon

connects epimysium to the periosteum

Tropomyosin

covers active sites of actin so myosin heads can't contact them

Epimysium

dense irregular CT around muscles

Prime Mover

muscle that produces the most force in an action

Thick filament

myosin

Extrinsic

palmaris longus muscle

Sarcolemma

plasma membrane of muscle fiber

Sarcomere

region between two z disks

I band

region of myofibril where there is no myosin, light striation

H band

region of sarcomere where myosin is located without actin

A band

region of sarcomere where myosin is located, dark striation

T tubules

regions of sarcolemma that dip deep into the muscle fiber

Flexion of the elbow fixator

rhomboids

Muscle fiber

skeletal muscle cells

SR

specialized smooth ER that stores and releases Ca++

Cardiac

striated, involuntary, intercalated disks

Skeletal

striated, voluntary

Flexion of the elbow antagonist

triceps brachii