Muscular System Flashcards
Describe the layers of a muscle
Fascia
Epimysium
Perimysium
Edomysium
Fascicle
Muscle fibres
Sarcolemma
Describe the size, shape and fibre arrangements of muscles
Convergent - starts small & fans out eg. pectoralis muscle
Fusiform - very thin paint brush tip, attaches to tendons at both ends eg hand forearm muscles
Parallel - straight, long strap like muscles eg. in the abs, legs
Circular - encircle body tubes or openings eg. mouth
Spiral - twists, flexible eg. neck to ribs
Pennate - different points of attachment, feather like apearance eg. shoulder, thighs calves
Describe size of muscles
Vastus - cluster of muscles that make up a big muscles
maximus - largest & heaviest muscle in the body
longus - long structure in body
minimus
brevis - latin for short
Describe the origin and insertion of muscles
Origin - stays put/ doesn’t move
insertion - moves when the muscle contracts
agonist - main mover
antagonist - resist muscle
synergist (fixator) - other muscles helping agonist
List the three characteristics of skeletal muscle tissue
Excitability
Contractability
Extensibility
Describe the structure and function of myofilaments
Each myofilament contains thousands of Thick + Thin filaments
4 proteins make up myofilaments:
Myosin (Think Filament) -
Actin (thin Filament) -
Tropomyosin - blocks active sites on actin molecules
Troponin - Holds tropomyosin in place
Distinguish between cardiac, smooth and skeletal muscles
Smooth - autorhythmic, produces peristalsis
Cardiac - Striated, involuntary muscle
Skeletal - contractability, extensibility & excitability
