A&P Ch10,11

• excitablility-stimili
• contractibility-shorten and thicken
• extensibility-stretched wo breaking
• elasticity-return to original shape

• motion
• posture
• heat production

• skeltal
• cardiac
• smooth

• voluntary
• striated

striated and involuntary

connects skin to muscle

• surrounds and suspends muscles and viscera
• 1-epimysium
• 2-perimysium
• 3-endomysium

outer sheath that surrounds each individual muscle- big

• surrounds each bundle of fibers w/i muscles
• (fasiculi)

surround individual muscle fibers in the fisiculi

longitudinal midanterior tendinous line from the zyphoid process to the symphisis pubis for abs

• aka epicranial
• tendous sheet for cranial insertion for upper scalp muscles

• cells/fibers
• sarcolema/plasma membrane

• multi nuclei
• sarcoplamic reticulum
• terminal sisterns
• transverse tubules
• myofibrils

• thick-composed of protein- myacine
• thin- = actin

ER of a muscle, job is to transport

terminal cisterns

extensions of the sarcolemma into the muscle fiber for fluids that contribute to fiber contraction

z lines or z disks

extends from one end to the other of the thick myofilaments. forms the dark striations in the sk. muscle

extends from the end of one thick filament to the beginning of the next. forms the light striations

w/i a band. contains thick but no thin myofilaments

runs down middle of H zone. composed of protein molecules that connect the centers of the thick myofilaments

• aka motor end plate
• where nerve meets muscle

• aka synaptic end bulb
• part of the nerve that lies in a pocket called synaptic cleft

pocket in sarcolemma where nerve axon terminal is

• neurotransmitter substance that is released at the neuromuscular junction in the synaptic cleft.
• it initiates the muscle action potential or muscle impulse

the muscle action potential travels over the sarcolemma and enters the transverse tubules triggering the sarcoplasmic reticulum to release it into the sarcoplasm

• mitochondria
• ATPase
• ATP
• ADP

cross bridges ratchet the thick and thin myofilaments in opposite directions

• the release of acetylcholinesterase in the synaptic cleft.
• cross bridges relax and muscles relax

oxygen required. longer than 10 min

• w/o oxygen.
• phosphogen system
• glycogen lactic acid system

has phosphocreatine that degrades to creatine with the release of energy. lasts 15 senconds

glycogen breaks down to pyruvate. 30-40 sec for strenous activity

record of muscle contraction

instrument that records muscle contraction

• latent
• contraction
• relaxation
• refractory

time btwn application of the stimulus and the beginning of contractions- 2 milli sec

the upward tracing

downward tracing

excitablity is temp. lost

• twitch- rapid jerky
• wave summation-2nd strong stimulus is applied befor the muscle relaxes

• unfused tetnus
• fused tetnus

• stimulation 20-30 times per sec.
• fibrilate or pulsate

• 80-100 pulsations per sec.
• can be- isotonic contractions, lifting weights
• -isometric, pushing wall

• frequency of stimulation
• # of contracting fibers
• components of the muscle fibers
• length of muscle fiber prior to contraction

less than normal tone

increased muscle tone

catbolic wasting away

anabolic increase in muscle size

• found only in heart.
• fibers are short and fat
• one centrally located nucleus
• striated
• possess intercalated disks

• hold fiber together with desmosomes.
• aid in conduction of action potentials through gap junctions

numerous mitochondria and the catabolism of glycogen

• cardiac
• smooth

cardiac

• nonstriated
• involuntary
• thick at center, taper at ends
• single central nucleus
• found in visera, organs, ateries, veins, branchioles, eye muscles

• skeltal- limited
• cardiac- none
• smooth- limited capacity for division and regeneration

inflammation of tendon sheaths and synovial membranes. commonly seen in wrist(carpol tunnel) and elbow(tennis elbow)

• lockjaw-bacterial illness that causes muscles to spasm.
• W/0 treatment die with a fixed smile and raised eyebrows

formation of fibrous connective tissue in muscles as a result of trauma and can cause neucrosis

gradual wasting of muscle tissue leading to death-genetic-amyotrophic lateral sclerosis (Lou Gehrig's or ALS) and Duchenne's

state of partial contraction of muscles following death. latck of ATP causes crossbridges to lock. Lasts 24 hrs disappears during 12hr period as tissue begins to decompose

skeletal mucsles and connective tissue

attachment to the stationary bone

attachment to the movable bone

central portion of muscle

joints

bones

force to be overcome

force to overcome resistance

fulcrom lies between effort and resistance (seesaw) atlanto occipital joint

fulcrom at one end at one end, effort at the opposite end, resitance between (tippy toes)

fulcrum at one end, resistance at opposite end and effort between (flexion of arm)

• strength increases with distance from the joint
• RoM decreases with distance from the joint

fascicules

• pennate- shorter
• parallel
• fusiform- taper like ftball
• convergent-broad to converge
• circular

(prime mover) muscle that causes a desired action

produces and opposite action

steadies a movement and makes it more effiecent

• direction of fibers
• location
• size
• number of origins
• shape
• origin/insertion
• action
• combination

frequently ruptures

stretching of the fascia

painful when ligments and muscles rub

• strains are to muscles or tendons
• sprains are to ligaments

rest, ice, heat, antiinflammitories