Muscular system 

functions of the muscular system- movement, tone, posture, protection

sphincters- circular muscles that control the openings in the digestive and urinary systems.

epimysium- a layer of collagen fibers that separate it from surrounding organs

fascicles- muscle is made up of these bundles

perimysium- divides each facile.

endomysium- surrounds each individual muscle fiber

tendon- a muscle attached to the bone

aponeurosis- muscle attached to another muscle.

sarcolemma- T-tubules, the cell membrane of the muscle fiber.

myofibers- long filaments that have the ability to contact

actin- thin, light filaments, type of protein

myosin- thick dark, filaments, type of protein

summation- the process of recruiting more muscle fibers to generate a greater force

latent period- the stimulus spreads through the muscle

contraction phase- actin and myosin generate tension

relaxation phase- actin and myosin uncouple and the muscle relaxes

ATP- the direct unit of energy used by muscle fibers

glycolysis- breaks down glucose, releasing two molecules of pyruvate and two molecules of ATP

Anaerobic- no oxygen is used

Aerobic- oxygen is used

lactic acid- a byproduct of fermentation and can cause fatigue and soreness

fermentation- reactions to recycle the unused products of glycolysis

properties of the muscular system- contractibility, extensibility, elasticity, and excitability

contractibility- the ability of muscle cells to shorten forcefully

extensibility- a muscle has the ability to be streched

elasticity- muscles have the ability to recoil back to t’s original length after being streched

excitability- muscle tissue responds to a stimulus delivered from a motor neuron hormone

periosteum- connective tissue that surrounds the bones

muscle tissue types- smooth, cardiac, skeletal

smooth- inside the organs

cardiac- line the heart wall, involuntarily

skeletal- bones, tendons, ligaments, voluntary

peristalsis- involuntary movement of the intestines, involuntary

Atrophy- waterway

Grade one muscle strain- (mild) little pain, a small amount of fiber damage, usually felt the next day of injury

Grade two muscle strain- (moderate) significant amount of muscle fibers torn, movement is limited by pain, strength is reduced, comes with swelling and pain

Grade three muscle strain- (severe) COMPLETE rupture/ tear of the muscle, loss of function, severe pain and swelling

Muscle contusions- a direct hit that causes a type of trauma/ hematoma, ex: bruises

Muscle cramp- involuntary movement, that occurs in the skeletal and smooth muscle and can last up to 7 days

Muscle soreness- delayed soreness usually after exercise

Rhabdomyolysis- serious injury due to direct or indirect muscle injury, death of muscle fibers, can cause kidney faliure then death if the fibers enter the bloodstream.