Anatomy & Physiology Exam Cram:
150+ Verified Questions for the 11th
Edition
Five General Functions of Skeletal Muscle - answer-Movement of the body and limbs,
maintenance of posture and body position, support of soft tissues (e.g., abdominal organs),
guarding body entrances and exits (sphincter control), and heat production through
contraction.
Five Characteristics of Skeletal Muscle - answer-Excitability (respond to stimuli), contractility
(ability to shorten), extensibility (ability to stretch), elasticity (return to original length),
conductivity (propagation of electrical impulses).
Sarcolemma - answer-Muscle fiber plasma membrane.
T-tubules - answer-Invaginations of sarcolemma that transmit action potentials into the fiber.
Sarcoplasmic Reticulum - answer-Specialized ER storing Ca²⁺.
Triad - answer-One T-tubule with two terminal cisternae of SR on either side.
Thick and Thin Filaments - answer-Thick filaments: myosin; Thin filaments: actin, tropomyosin,
troponin.
Organization of Myofibrils, Myofilaments, Sarcomeres - answer-Myofibrils are bundles of
1
, myofilaments; sarcomeres are repeating contractile units of myofibrils; myofilaments are the
actin and myosin filaments.
Structures Associated with Energy Production - answer-Mitochondria for aerobic respiration,
creatine phosphate for rapid ATP, glycogen stores for glucose.
Motor Unit - answer-One motor neuron plus all muscle fibers it innervates; size varies with
precision needs (small = fine control, large = gross movement).
Three Components of Neuromuscular Junction - answer-Synaptic knob/axon terminal, motor
end plate, synaptic cleft.
ACh Release Events - answer-Action potential arrives → Ca²⁺ enters axon terminal → synaptic
vesicles release ACh → ACh binds to receptors on motor end plate → Na⁺ influx triggers muscle
action potential.
Excitation-Contraction Coupling Steps - answer-Action potential travels along sarcolemma →
down T-tubules → SR releases Ca²⁺ → Ca²⁺ binds troponin → tropomyosin moves → myosin
binds actin → crossbridge cycle begins.
Changes in Sarcomere During Contraction - answer-Z-discs move closer, I-band shortens, H-zone
disappears, A-band remains constant.
Skeletal Muscle Relaxation - answer-ACh is degraded by acetylcholinesterase, action potential
stops, Ca²⁺ pumped back into SR, troponin-tropomyosin blocks actin binding sites.
ATP Availability - answer-Creatine phosphate quickly regenerates ATP, glycolysis produces ATP
anaerobically, aerobic respiration produces ATP with oxygen.
2
150+ Verified Questions for the 11th
Edition
Five General Functions of Skeletal Muscle - answer-Movement of the body and limbs,
maintenance of posture and body position, support of soft tissues (e.g., abdominal organs),
guarding body entrances and exits (sphincter control), and heat production through
contraction.
Five Characteristics of Skeletal Muscle - answer-Excitability (respond to stimuli), contractility
(ability to shorten), extensibility (ability to stretch), elasticity (return to original length),
conductivity (propagation of electrical impulses).
Sarcolemma - answer-Muscle fiber plasma membrane.
T-tubules - answer-Invaginations of sarcolemma that transmit action potentials into the fiber.
Sarcoplasmic Reticulum - answer-Specialized ER storing Ca²⁺.
Triad - answer-One T-tubule with two terminal cisternae of SR on either side.
Thick and Thin Filaments - answer-Thick filaments: myosin; Thin filaments: actin, tropomyosin,
troponin.
Organization of Myofibrils, Myofilaments, Sarcomeres - answer-Myofibrils are bundles of
1
, myofilaments; sarcomeres are repeating contractile units of myofibrils; myofilaments are the
actin and myosin filaments.
Structures Associated with Energy Production - answer-Mitochondria for aerobic respiration,
creatine phosphate for rapid ATP, glycogen stores for glucose.
Motor Unit - answer-One motor neuron plus all muscle fibers it innervates; size varies with
precision needs (small = fine control, large = gross movement).
Three Components of Neuromuscular Junction - answer-Synaptic knob/axon terminal, motor
end plate, synaptic cleft.
ACh Release Events - answer-Action potential arrives → Ca²⁺ enters axon terminal → synaptic
vesicles release ACh → ACh binds to receptors on motor end plate → Na⁺ influx triggers muscle
action potential.
Excitation-Contraction Coupling Steps - answer-Action potential travels along sarcolemma →
down T-tubules → SR releases Ca²⁺ → Ca²⁺ binds troponin → tropomyosin moves → myosin
binds actin → crossbridge cycle begins.
Changes in Sarcomere During Contraction - answer-Z-discs move closer, I-band shortens, H-zone
disappears, A-band remains constant.
Skeletal Muscle Relaxation - answer-ACh is degraded by acetylcholinesterase, action potential
stops, Ca²⁺ pumped back into SR, troponin-tropomyosin blocks actin binding sites.
ATP Availability - answer-Creatine phosphate quickly regenerates ATP, glycolysis produces ATP
anaerobically, aerobic respiration produces ATP with oxygen.
2
