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