click below
click below
Normal Size Small Size show me how
Muscular Ex Rev
Muscular System Review
| Question | Answer |
|---|---|
| List 4 functions of skeletal muscle | movement, posture heat production, joint stability |
| List 4 characteristics of skeletal muscle tissue | excitability-ability to receive and respond to stimulus contractility- ability to shorten or compact extensibility- ability to stretch or lengthen elasticity- ability to return to its original shape and length |
| endomysium | connective tissue that surrounds each individual muscle cell/fiber |
| perimysium | layer of connective tissue that surrounds the fasciculus (bundle of cells) |
| epimysium | connective tissue sheath that surrounds a muscle |
| acetylcholine | a neurotransmitter. A chemical substance that is released at the axon terminals of many neurons to carry the impulse across a synaptic cleft |
| tendon | a band of dense fibrous connective tissue that attaches muscle to bones |
| aponeurosis | a sheet of tendon like material, serves as an attachment for muscle to bone and other tissue |
| origin | end of a muscle that is attached to a bone that is stationary; the end Opposite the insertion |
| insertion | the end of a muscle that is attached to a bone or cartilage that moves; the end opposite the origin |
| What happens during contraction | muscle fiber gets shorter and thicker |
| What happens to muscle fiber during relaxation | they get longer and thinner |
| How do skeletal muscles move bones | by pulling on the bones; they never push |
| flexion (to bend) | decreasing angle between 2 bones Bending elbow or knee |
| extension (to straighten) | increasing angle between 2 bones straightening elbow or knee |
| abduction (take away) | to move a bone or limb away from the midline or axis of the body "jumping jacks" |
| adduction (bring together) | moves a bone or limb toward the midline of the body. arms back to side of body |
| rotation | movement of bone around its own axis in a pivot joint "shaking head no" |
| dorsiflexion | backward bending of the foot (toes up) "standing on heels" |
| plantar flexion | pointing sole of foot downward "standing on toes" |
| pronation | facing downward (hand-palm down/inferior) |
| supination | facing upward (hand-palm up/superior) |
| hyperextension | extreme or abnormal extension (extension of knee with plantar flexion) |
| circumduction | conelike circular movement of a body segment movement of arm at shoulder joint with elbow extended; finger tips move in a circle |
| orbicularis oculi | circular muscle around the eyes closes the lid |
| zygomaticus | extends diagonally from the corner of the mouth to the cheekbone elevates corners of mouth for smiling |
| buccinator | horizontal cheek muscle compresses cheek for blowing; trumpeter's muscle |
| masseter | covers lateral aspect of the jaw closes the mouth, elevates mandible |
| pectoralis major | large fan-shaped muscle that covers the anterior chest adducts the arm across chest |
| deltoid | thick muscle that forms contour of the shoulder flexes, abducts, extends arm |
| biceps brachii | major muscle in the anterior compartment of arm; has 2 heads flexes and supinates/flexes elbow |
| triceps brachii | only muscle in posterior compartment of arm; has 3 heads extends elbow |
| rectus abdominis | long, straight muscle on each side of the linea alba compresses abdomen and flexes trunk |
| gluteus maximus | largest gluteal muscle/buttocks extends thigh |
| quadricep group | group of 4 muscle that form the mass of the anterior thigh; forms a common tendon that passes over patella extends knee, flexes thigh |
| name 4 quadricep muscles | rectus femoris vastus lateralis vastus medialis vastus intermedius |
| hamstring group | large muscle in the posterior thigh flexes leg and extends thigh |
| name 3 hamstring muscles | biceps femoris semimembranosus semitendinosus |
| gastrocnemius | superficial muscle on the posterior surface of leg; forms curve of calf flexes knee/points toes |
| atrophy | a decrease in size of muscle fibers or a wasting away of muscles from poor nutrition, lack of use, motor unit dysfunction, or lack of motor nerve impulses |
| isometric | muscle contraction without movement |
| cramp (spasm) | increase in muscle tension with or without shortening due to excessive motor nerve activity may result in a knot; often associated with mineral deficiency or muscle fatigue |
| myositis | inflammation of voluntary muscle |
| sprain | trauma to a joint with injury to ligaments and/or tendons |
| strain | "overstretched muscle" commonly called a pull, an injury of a muscle or tendon due to a violent contraction, forced stretching |
| tic | an involuntary twitching of a muscle |
| twitch | muscle contraction from a single stimulus |
| paralysis | loss of sensation/voluntary movement, may be temporary or permanent |
| hemiplegia | paralysis on on side of the body |
| paraplegia | paralysis of the lower extremities and any degree of trunk |
| quadriplegia | paralysis of all four extremities |
| paresis | partial paralysis |
| what is muscular dystrophy | chronic progressive muscle disorder, causes progressive muscle weakness and atrophy |
| what is myasthenia gravis | neuromuscular disorder caused by not enough acetylcholine. Starts in face |
| what muscles does myasthenia gravis affect | eye (ptyosis); mastication; pharyngeal; respiratory |
| signs and symptoms of myasthenia gravis | drooping facial muscles; drooping upper eyelids; double vision; drooping throat; difficulty chewing or swallowing; slurred speech |
| what is polymositis | inflammatory disease of multiple skeletal muscles; pain, weakness, chronic |
| what is rhabdomyoma | striated muscular tissue tumor |
| muscle biopsy | removal of muscle tissue for microscopic examination |
| EMG | electromyogram; recording of muscular reactions when given electrical stimulation |
| IM | intramuscular |
| sternocleidomastoid | straplike muscle that ascends obliquely over neck laterally flexes and rotates head sternum, clavicle, mastoid attachment |