MUSCULAR SYSTEM Flashcards
responsible for all types of body movement
MUSCLES
attached by tendons to bones
SKELETAL MUSCLE
obvious stripes
STRIATED MUSCLE
only muscle tissue subject to conscious control
VOLUNTARY MUSCLE
encloses a single muscle fiber
ENDOMYSIUM
wraps around a fascicle of muscle fibers
PERIMYSIUM
covers the entire skeletal muscle
EPIMYSIUM
on the outside of the epimysium
FASCIA
found only on the walls of heart
CARDIAC MUSCLE
branching cells joined by gap junctions
INTERCALATED DISCS
mainly in the walls of hollow visceral organs
SMOOTH MUSCLE
specialized plasma membrane
SARCOLEMMA
long organelles inside muscle cell
MYOFIBRILS
light band
l band
dark band
A band
midline interruption
Z LINE
lighter central area
H ZONE
center of H zone
M LINE
contractile unit of a muscle fiber
SARCOMERE
thick filaments, composed of the protein myosin
MYOSIN FILAMENTS
thin filaments, composed of the contractile protein actin
ACTIN FILAMENTS
specialized smooth endoplasmic reticulum
SARCOPLASMIC RETICULUM
4 MAJOR FUNCTIONAL PROPRIETIES
CONTRACTILITY
EXCITABILITY / IRRITABILITY
EXTENSIBILITY
ELASTICITY
the ability of the muscle to shorten forcefully or contract
CONTRACTILITY
the capacity of muscles to respond to an electrical stimulus
EXCITABILITY / IRRITABILITY
means a muscle can be stretched beyond its normal resting length and still be able to contract
EXTENSIBILITY
the ability of muscle to spring back to its original resting length after it has been stretched
ELASTICITY
gap between nerve and muscle filled with interstitial fluid
SYNAPTIC CLEFT
contract to its fullest when stimulated adequately.
GRADED RESPONSE
Graded responses can be produced in two ways
changing the frequency of muscle stimulation
changing the number of muscle cells being stimulated at one time
single, brief, jerky contraction
MUSCLE TWITCH
in most types of muscle activity, nerve impulses are delivered at a rapid rate
SUMMING OF CONTRACTIONS
muscle contractions get stronger and smoother
UNFUSED TETANUS
muscle is stimulated so rapidly that no evidence of relaxation is seen
FUSED TETANUS
the only energy source that can be used to directly power muscle contraction
ATP
Three pathways to regenerate ATP
- Direct phosphorylation of ADP by creatine phosphate
- Aerobic pathway
- Anaerobic glycolysis and lactic acid formation
supplies ATP at rest and during light/moderate exercise
AEROBIC RESPIRATION
reaction that breaks down glucose without oxygen
ANAEROBIC GLYCOLYSIS / LACTIC ACID FORMATION
TYPES OF MUSCLE CONTRACTIONS
ISOTONIC CONTRACTION
ISOMETRIC CONTRACTION
myofilaments are able to slide past each other during contractions
the muscle shortens, and movement occurs
ISOTONIC CONTRACTION
muscle filaments are trying to slide, but the muscle is pitted against an immovable object
ISOMETRIC CONTRACTION
results from the production of antibodies that bind to acetylcholine receptors,
MYASTHENIA GRAVIS
MUSCLE FUNCTIONS
Movement of the body
Maintenance of posture
Respiration
Production of body heat
Communication
Construction of organs and vessels
Contraction of the heart
