Muscular System Notes

cardiac muscle

striated, involuntary

smooth muscle (visceral)

involuntary, non-striated- found in walls of hollow organs, blood vessels, and sphincter muscles

skeletal muscle

striated, voluntary- contractions, cause movement

irritability of skeletal muscle

The ability to react to a stimulus

contractility of skeletal muscle

ability to shorten when stimulated

extensibility of skeletal muscle

ability to stretch

elasticity of skeletal muscle

ability to return to the normal length

what incases skeletal muscle?

connected tissue sheath and connective tissue attachments at the end of the muscle

facia

each muscle is encased by this fibrous connective tissue sleeve

tendon

fibrous connective tissue band that attaches muscle to bone

Origin

The attachment with little to no movement

insertion

attachment that moves the most

Apoheurosis

A broad fiber sheet of connective tissue that attaches a muscle to band of muscle

epimysium

covers the whole muscle

Perimysium

surrounds and separates a large group of fibers of a muscle called fasicis

endomysium

surrounds each individual muscle fiber

what is each muscle cell considered?

a fiber

sarcolemma

muscle cell membrane

sarcoplasm

cytoplasm of muscle cell

smaller component of fiber

myofibrils

myofibrils smaller unit

myofiaments- actin (thin) myosin (thick)

Sarcomere

contractile unit of skeletal muscle