Muscular system- regions on a muscle organ, skeletal muscle classification

epimysium

a dense layer of collagen fibers that surround the skeletal muscle

perimysium

connective tissue encircling a single skeletal muscle fascicle

endomysium

a delicate network of connective tissue fibers that surround individual muscle cells

Fascicle

a bundle of skeletal muscle cells (fibers)

myofilaments

contractile protein filaments consisting of mainly actin and myosin

thin myofilament

actin

thick myofilament

myosin

myofibril

bundles of myofilaments found in a single muscle cell

neuromuscular junction

a synapse between a neuron and a muscle cell

sarcolemma

plasma membrane of a skeletal muscle fiber (cell)

sarcoplasmic reticulum

skeletal muscle cell of endoplasmic reticulum

aponeuroses

flattened tendinous sheet derived from interwoven fibers of the endomysium, perimysium, and epimysium of the skeletal muscle

T-tubule

transverse tubular extensions of the sarcolemma that extend deep into the sarcoplasmic reticulum to contract cisternae of the sarcoplasmic reticulum.

sarcomere

regions that repeat along the length of the skeletal muscle fiber and for a functional unit of contraction

terminal cisternae

pairs of transversely oriented tubules of SR in skeletal muscle that together with a t-tubule form a triad

parallel

fascicles parallel along axis of muscles, example sartorius

unipennate

all fascicles converge to one slide of the tendon example: semimembranosus

Bipennate

fascicles converge to both sides of tendon, example rectus femorus

multipennate

tendon branches converge to a single tendon (deltiod)

convergent

fascicles spread over a large area converge to a single tendon (pectoralis major)

circular

concentrically arranged fibers surrounding an opening (orbicularis oris)

parallel with tendinous bands

fascicles parallel to muscle long axis with perpendicular connective tissue strips that divide up length (rectus abdominis)

wrapping

fascicles parallel to muscle long axis will wrap around a bone, usually near joints (supinator)