muscular system (chapters 10-11)

skeletal muscle

band like appearance and dark and light stripes

long fibers

separate cells (hard to see)

many cell nucleus present

voluntary muscle

moves bones

multi nucleated

striated

cylindrical

found in arms and legs

smooth muscle

not connected to bones

easier to see individual cells

involuntary muscle

single nucleated

nonstriated (because of tapered ends)

non cylindrical

found in digestive system and arteries

cardiac muscle

long fibers form a weave by joining together

involuntary

connected to bone

single nucleated

striated

cylindrical

only found in heart

properties of muscular tissue

electrical excitability

contractibility

extensibility

elasticity

electrical excitability

the signal an action potential originates in the nervous system and is transferred to neuro-muscular junction allowing contraction of the muscle

contractability

the ability of muscle to contract forcefully when stimulate by an action potential

extensibility

the ability to stretch (within limits) without damage

elasticity

the ability of muscle tissue to return to its original length and strength after each contraction or extension

fascia

dense sheet of irregular connective tissue that lines the body wall and limbs and supports and surrounds other organs and muscles

epimysium

encircles the entire muscle with dense irregular connective tissue

perimysium

surrounds group of 10-100 muscle fibers separating them into bundles called fascicles

fascicles

bundles made by perimysyium, meat tears along these lines

endomysium

separates individual muscle fibers

capillaries

microscopic blood vessels

brings in oxygen and nutrients

removes heat and waste products of muscle metabolism

sarcolemma

plasma membrane of muscle cell

contains transverse tubules

transverse tubes

t tubes

fill with interstitial fluid

helps action potential pass easily along the muscle fiber

sarcolemma

specialized plasma membrane of a muscle fiber (cell) that surrounds the sarcoplasm and acts as a barrier between the intracellular and extracellular compartments

myofibrils

have striations that make the muscle look striped

stemocleidomastoid

name is derived from its three points of attachment: the sternum (sterno), clavicle (cleido), and the mastoid process of the skull

external oblique

the largest and most superficial of the three flat muscles in the lateral abdominal wall. It plays a critical role in trunk movement, core stability, and the protection of internal organs. 

transversal abdominus

provides structural support to adjacent abdominal structures
compresses abdomen and increases intrabdominal pressure

rectus abdominus

flexes the trunk
tenses the anterior abdominal wall

gluteous

hip hip extension

hip lateral rotation

helps with hip abduction