Skeletal Muscle Flashcards
(12 cards)
Contractile elements
Actin Myosin Banding Z-lines (between Disks) M-lines (middle) H-lines (helles)
Sarcoplasmic Reticulum
Modified ER
Calcium Ion storage
(Depolarization triggers release)
Fiber Type-I
Slow twitch
Fatigue resistant
Fiber Type-II
Fast twitch
Fatiguable
Motor Units
Neurons
Muscle Stimulation
Nerve impulses release acytlcholme into muscle cell
Opening of gates causes depolarization
Depolarization causes Sarcoplasmic Reticulum Ion channel to open
Muscle Contraction
Calcium binds to tropinin
Myosin binds to actin and tilts creating the power stroke
Myosin disassociates and head returns to normal position
Origin (attachment)
Fixed
Insertion (attachment)
Mobile
Belly (attachment)
Thickened middle portion
Synergistic
Groups that work together
Antagonistic
Groups with opposing actions
I.e. opposite sides of limbs