Chapter 5 System 3 Muscular System Flashcards
muscles comprise what % of body weight?
40% - 60%
elasticity
The tissues ability to return to normal resting length when a stress that has been placed on it is removed
extensibility
Is the ability of a muscle to stretch
irritability
Or excitability, is the capacity of muscles to receive and react to stimuli
which cells produce nearly all the movement in the body?
Muscle cells
Contractility
Is the ability of a muscle to contract or shorten and thereby exert force
superficial fascia
Situated just below the skin and covers the entire muscular system
deep fascia
The fascia penetrates to the bone, separating muscle groups and covering individual muscles
skeletal muscle
Striated and voluntary CNS (central nervous system)Cigar shapedMakes up fleshy areas of the body Attached to the skeleton, and are in turn fastened to the bones, skin, or other muscles
smooth muscle
Visceral Smooth and involuntary ANS (autonomic nervous system) Spindle shaped, nonstriated cells that overlap at the ends Doesn’t attach to boneSlow actingCan maintain a contraction for a long time Doesn’t fatigue easily
cardiac muscle
Found only in the heart Striated and involuntaryCells are quadrangular, joined end to end, and grouped in bundles supported by a frame work of connective tissue
Are muscle cells multinucleated?
Yes, a single cell can have hundreds of nuclei distributed just beneath the cell membrane. These nuclei produce the enzymes and proteins necessary in muscle contraction
spindle cells
Specialized muscle cells that have both sensory and motor functions are essential for muscle control and coordination.
Located in the belly of a muscle, alert the CNS as to the length, stretch, and speed of the muscle
how long can ATP sustain a contraction?
There is only enough ATP stored in the muscle cells to sustain a contraction for a few seconds. Within a fraction of a second, ADP is reconstituted into ATP in one of several ways
how many muscles are in the body?
Over 600 muscles, large and small
what are the 4 characteristics of muscles?***
ICEE
Irritability or excitability. Contractility.
Elasticity.
Extensibility.
endomyium
Within the fascicle, each muscle fiber has a delicate connective tissue covering Maintains its parallel position with other cells
tendon
Fibrous connective tissue bands that attach muscle to bone
ligament
Bands of fibrous tissue that connect bones to bones
neuromuscular junction
Myoneural junctionThe site where the muscle fiber and nerve fiber meet
sarcomere
The smallest functional unit of the muscle cell containing the actin and myosin filaments A band (dark, thick myosin filament)-M line-H zone-overlap zoneI band (light, thin actin filaments)-Z line
muscle fatigue
Is a condition in which the muscle ceases to respond because of oxygen debt from rapid or prolonged muscle contractions
muscle fibers types (I, II)
Type I.
Slow twitch Slow to fatigue Slow contraction Lots of mitochondriaLots of myoglobinPostural musclesType IIFast twitchFast to fatigueFast contractions (5x-10x faster)Little mitochondriaLittle myoglobinArms, legs, shoulders***chicken white breast meat
white breast meat of chicken, which fibers of muscle make it up?
Type II fibers
phasic muscle
Contains a higher proportion of type II fibersUsed for quick, infrequent, powerful movementMovers
postural muscle
Contains a higher proportion of type I fibersStabilizersSupport the body against gravity. Slower to respond to stimulation Slower to fatigue
origin and insertion
Origin of a muscle is the point where the end of a muscle is anchored to an immovable section of the skeleton.Insertion of a muscle is the more movable attachment of a muscle to bone.
isometric contraction
Occurs when a muscle contracts and the ends of the muscle do not move
isotonic contraction
Occurs when a muscle contracts and the distance between the ends of the muscle changes Concentric or eccentric
concentric
In an isotonic contraction the distance between the ends of the muscle decreases
eccentric
In an isotonic contraction the distance between the ends of muscle increases
what muscle action occurs when you do a push up?
As you push up, the loaded muscles shorten, and is a concentric contractionAs you lower yourself to the floor , the loaded muscles are getting longer and is an eccentric contraction
agonist
A prime moverThe primary muscle responsible for a specific movement
antagonist
The muscle that performs the opposite movement of the agonist
synergist
Muscles that assist the agonist
Clonic
When spasms alternate between contraction and relaxation
spasm
Most common muscle dysfunction Is a sudden involuntary contraction of a muscle or a group of muscles. Vary in duration and intensityCan affect any muscle tissue (vol., invol., card.)I.e. Cramps, hiccups, tics, fast face twitches, torticollis, Charlie horse, convulsions, muscle splinting.
Tonic
When spasms are sustained
massaging over charlie horses
Massage directly on the site of an acute cramp or Charlie horse is contraindicated
sprain
is an injury to a joint that results in the stretching or tearing of the ligaments but not severe enough to cause a dislocation
strain
also called torn or pulled musclemost common injury to musclecontraindicated during the acute stages of muscle strain
where do the majority of muscle strains occur?
80% of muscle strains occur in the muscle belly or at the junction between the muscle and the tendon (musculotendinous junction)
hypertrophy
is an enlargement of the breadth of a muscle as a result of repeated forceful muscle activity
contractures
are shortened, contracted muscles or muscle groups in which the muscle atrophies and shrinks while the connective tissue thickens.related to immobility or severe nerve damagemessage is beneficial in the early stages along with regular stretching
Sarcolemma
Is the cell wall of the muscle cell
fibromyalgia syndrome
characterized by pain, fatigue, and stiffness in the connective tissue of the muscles, tendons, and ligaments. associated with stress, poor sleep habits, and occupational or recreational strain.more prevalent in women.massage to desensitize trigger points and range of motion exercises are beneficialmassage should be gentle and done with great consideration of the condition.work in conjunction with clients physician
Myosin
ThickA protein that forms filamentsMakes up nearly 50% of muscle tissue Involved in muscle contraction
lupus erythematosus
is a chronic inflammatory disease of the connective tissue that can affect many body tissues and organs.autoimmune disorder that causes blood vessel inflammation, organ dysfunction, and arthritis.massage may be given only under the supervision of a physician
Actin
ThinA protein that forms a filamentInteracts with myosin to cause muscle contractions
transverse tubules
a system of channels within the muscle cell containing extracellular fluid that helps transmit nerve impulses throughout the cell
sacroplasmic reticulum
is a network of membranous channels within the muscle cell that release calcium ions, causing muscle contraction
sliding filament theory
the actin filaments slide across the myosin filaments to cause contraction
motor unit
consists of a motor neuron and all of the muscle fibers it controls
when a nerve impulse travels from the brain or spinal cord through the motor neuron and reaches the end of the nerve fiber, a chemical neurotransmitter called ____ is released and bridges the gap between the nerve end and muscle fiber
acetylcholine
creatine phosphate
even though the energy cannot be used directly by the muscle, the energy causes the rebonding of the phosphate ion, producing ATP
Aerobic cellular respiration
most of the energy to reconstitute ADP is the result of cellular respirationtakes place in the cells mitochondria
krebs cycle
citric acid cyclein the mitochondria, a complex metabolic process takes place, resulting in the production of carbon dioxide, water, and energy in the form of heat and the synthesis of ATP
anaerobic respiration
is a process in which glucose is broken down in the absence of oxygensynthesizes some ATP and produce pyruvic acid, which is converted to lactic acid, which is carried by the bloodstream to the liver, where it is converted back to glucose
oxygen debt
less efficient anaerobic respiration produces pyruvic and then lactic acid. As lactic acid accumulates, the person develops oxygen debt
the 3 components of motion
flexion / extensionabduction / adductionrotation
Describe the 3 grades of strains
grade 1 overstreching of a few muscle fibers with minimal fiber tears. some pain, no loss of function. no palpable or visual indicationsgrade 2 tearing between 10%-50% of the muscle fibers. pain. some loss of function. palpable thickening of the muscle tissue. possible tissue bleedinggrade 3 tearing between 50%-100% of muscle fibers. palpable depression and / or bunching of the muscle. severe pain. total or near total loss of function
what is the preferred intervention during the acute stage of a muscle strain, which can last 24-72 hours depending on the severity.
PRICEprotectresticecompresselevate
tendonitis and tenosynovitis
tendonitis is an inflammation of the tendon often occurring at the musculotendinous or tenoperiosteal junctiontenosynovitis is an inflammation of the tendon sheathmany times they occur simultaneously.contraindicated on the lesion during the acute stages of inflammation
tendonosis
is a degenerative condition of a tendon that does not involve any inflammation. characterized by the degeneration of the collagen fibers in the tendon, tendon weakness, and abnormal growth of unhealthy blood vessels through the tendon
dystrophy
a group of related diseases that seem to be genetically inherited and cause progressive degeneration of the voluntary muscular systemthe contractile fibers of the muscles are gradually replaced by fat and connective tissue until those muscles become useless
