Anatomy & Physiology - CH9A NS#2

fascia

layers of dense connective tissue separating muscles and stabilize their position

subcutaneous

immediately under the skin

deep

lines the body wall and limbs (usually together)

tendon

projects of fascia at the ends of a muscle that attach to bone

aponeurosis

flat, fibrous sheets attaching to other muscles or bone

epimysium

sheath covering the whole muscle

perimysium

extends inward from the epimysium and separates muscle tissue into smaller bundles

fascicles

muslce bundles

endomysium

weaves in between each bundle separating individual muscle fibers

muscle fibers

form from undifferentiated cells that fuse together

myofibrils

small parallel fibers in muscle fibers; produces the alternating light and dark bands with parts called myolfilaments

actin

thin filaments

myosin

thick filaments

sarcomeres

the striations from myofilaments form a repeating pattern

I-Band

light bands due to containing thin filaments (actin) only

Z-Line

separate one sarcomere from the next

A-Band

dark bands due to presence of many thick filaments (myosin) overlapping thin filaments

H-Zone

slightly lighter region within the A-Band; contains thick filaments only

M-Line

Thickening of the A-Band (proteins)

titin

protein that attaches the myosin filaments to the z-line

cross bridges

two twisted protein strands with globular heads on each myosin molecule

sarcoplasmic reticulum (SR)

network of channels running parallel and surrounding each myofibril

transverse tubules

extends through the sarcoplasm containing ECF