KINES 350 EXAM 3 QUESTIONS ANSWERED CORRECTLY LATEST UPDATE 2026
Work-induced hypertrophy - Answers Muscle fiber growth caused by exercise where fiber diameter
increases without increasing fiber number.
Sarcopenia - Answers Age-related loss of skeletal muscle mass and strength.
Muscle loss 25-50 yrs - Answers About 10% muscle mass lost.
Muscle loss 50-80 yrs - Answers About 40% additional muscle mass lost.
Training that slows sarcopenia - Answers Resistance training.
Cancer cachexia - Answers Rapid muscle wasting seen in ~50% of cancer patients.
Cancer deaths linked to cachexia - Answers ~20%.
Duchenne muscular dystrophy - Answers Most common childhood muscular dystrophy caused by
genetic muscle protein defects.
Muscle fiber - Answers A single multinucleated muscle cell.
Sarcolemma - Answers Muscle fiber cell membrane.
Sarcoplasm - Answers Cytoplasm inside muscle fibers.
Myofibrils - Answers Contractile bundles inside muscle fibers composed of actin and myosin.
Sarcomere - Answers Functional contractile unit of skeletal muscle.
Actin - Answers Thin filament involved in muscle contraction.
Myosin - Answers Thick filament responsible for power stroke.
Determinant of muscle fiber size - Answers Balance between protein synthesis and protein
degradation.
Muscle hypertrophy - Answers Synthesis of muscle protein exceeds degradation.
Muscle atrophy - Answers Protein degradation exceeds protein synthesis.
Total muscle protein synthesis - Answers Number of myonuclei × synthesis rate per nucleus.
Protein turnover - Answers Continuous synthesis and degradation of proteins.
Daily body protein turnover - Answers ~280 g/day.
Energy cost of protein turnover - Answers ~20% of resting energy expenditure.
Muscle contribution to total protein turnover - Answers ~30%.
Fractional synthesis rate (FSR) - Answers Rate of new protein production.
Mixed muscle protein FSR - Answers ~1.15% per day.
Mitochondrial protein FSR - Answers ~2.5% per day.
Highest protein synthesis rate - Answers VLDL apo-B100 (~425% per day).
Ways muscle protein content changes - Answers Gene expression changes, mRNA breakdown,
selective translation, selective protein degradation.
Transcription - Answers DNA → mRNA.
Translation - Answers mRNA → protein at ribosome.
Resistance exercise effect on muscle protein synthesis - Answers Significant increase in muscle protein
synthesis.
Protein ingestion + resistance training - Answers Increases muscle protein synthesis further.
Endurance exercise effect on muscle protein synthesis - Answers Small decrease or no change during
exercise.
Post-endurance exercise protein changes - Answers Increased mitochondrial protein synthesis.
Neuromuscular fatigue causes - Answers Glycogen depletion, acetylcholine changes, ion imbalance,
H+ accumulation.
Motor unit - Answers Motor neuron plus all muscle fibers it innervates.
Size principle - Answers Motor units recruited from smallest to largest.
First motor units recruited - Answers Type I slow-twitch fibers.
Last motor units recruited - Answers Type II fast-twitch fibers.
Resting membrane potential - Answers Negative electrical charge inside cells at rest.
Typical neuronal resting membrane potential - Answers −40 to −75 mV.
Ions controlling membrane potential - Answers Na+, K+, Cl−, Ca2+.
Na+/K+ pump - Answers 3 Na+ out and 2 K+ into cell.
Depolarization - Answers Na+ channels open and Na+ enters cell.
Repolarization - Answers K+ exits the cell restoring resting potential.
All-or-none law - Answers Once initiated, action potential travels entire neuron.
EPSP - Answers Excitatory postsynaptic potential making neuron more likely to fire.
IPSP - Answers Inhibitory postsynaptic potential making neuron less likely to fire.
Work-induced hypertrophy - Answers Muscle fiber growth caused by exercise where fiber diameter
increases without increasing fiber number.
Sarcopenia - Answers Age-related loss of skeletal muscle mass and strength.
Muscle loss 25-50 yrs - Answers About 10% muscle mass lost.
Muscle loss 50-80 yrs - Answers About 40% additional muscle mass lost.
Training that slows sarcopenia - Answers Resistance training.
Cancer cachexia - Answers Rapid muscle wasting seen in ~50% of cancer patients.
Cancer deaths linked to cachexia - Answers ~20%.
Duchenne muscular dystrophy - Answers Most common childhood muscular dystrophy caused by
genetic muscle protein defects.
Muscle fiber - Answers A single multinucleated muscle cell.
Sarcolemma - Answers Muscle fiber cell membrane.
Sarcoplasm - Answers Cytoplasm inside muscle fibers.
Myofibrils - Answers Contractile bundles inside muscle fibers composed of actin and myosin.
Sarcomere - Answers Functional contractile unit of skeletal muscle.
Actin - Answers Thin filament involved in muscle contraction.
Myosin - Answers Thick filament responsible for power stroke.
Determinant of muscle fiber size - Answers Balance between protein synthesis and protein
degradation.
Muscle hypertrophy - Answers Synthesis of muscle protein exceeds degradation.
Muscle atrophy - Answers Protein degradation exceeds protein synthesis.
Total muscle protein synthesis - Answers Number of myonuclei × synthesis rate per nucleus.
Protein turnover - Answers Continuous synthesis and degradation of proteins.
Daily body protein turnover - Answers ~280 g/day.
Energy cost of protein turnover - Answers ~20% of resting energy expenditure.
Muscle contribution to total protein turnover - Answers ~30%.
Fractional synthesis rate (FSR) - Answers Rate of new protein production.
Mixed muscle protein FSR - Answers ~1.15% per day.
Mitochondrial protein FSR - Answers ~2.5% per day.
Highest protein synthesis rate - Answers VLDL apo-B100 (~425% per day).
Ways muscle protein content changes - Answers Gene expression changes, mRNA breakdown,
selective translation, selective protein degradation.
Transcription - Answers DNA → mRNA.
Translation - Answers mRNA → protein at ribosome.
Resistance exercise effect on muscle protein synthesis - Answers Significant increase in muscle protein
synthesis.
Protein ingestion + resistance training - Answers Increases muscle protein synthesis further.
Endurance exercise effect on muscle protein synthesis - Answers Small decrease or no change during
exercise.
Post-endurance exercise protein changes - Answers Increased mitochondrial protein synthesis.
Neuromuscular fatigue causes - Answers Glycogen depletion, acetylcholine changes, ion imbalance,
H+ accumulation.
Motor unit - Answers Motor neuron plus all muscle fibers it innervates.
Size principle - Answers Motor units recruited from smallest to largest.
First motor units recruited - Answers Type I slow-twitch fibers.
Last motor units recruited - Answers Type II fast-twitch fibers.
Resting membrane potential - Answers Negative electrical charge inside cells at rest.
Typical neuronal resting membrane potential - Answers −40 to −75 mV.
Ions controlling membrane potential - Answers Na+, K+, Cl−, Ca2+.
Na+/K+ pump - Answers 3 Na+ out and 2 K+ into cell.
Depolarization - Answers Na+ channels open and Na+ enters cell.
Repolarization - Answers K+ exits the cell restoring resting potential.
All-or-none law - Answers Once initiated, action potential travels entire neuron.
EPSP - Answers Excitatory postsynaptic potential making neuron more likely to fire.
IPSP - Answers Inhibitory postsynaptic potential making neuron less likely to fire.
