1/9
Flashcards covering essential concepts of skeletal muscle contraction, excitation-contraction coupling, and muscle metabolism.
Name | Mastery | Learn | Test | Matching | Spaced |
---|
No study sessions yet.
What is the sliding filament mechanism of muscle contraction?
Muscle contraction occurs when thick and thin filaments slide past each other, resulting in sarcomere shortening.
What initiates the muscle contraction-relaxation cycle?
The increase in sarcoplasmic Ca2+ concentration triggers muscle contraction, while the decrease leads to relaxation.
What role does calcium play in the sliding filament mechanism?
Calcium binds to troponin C, causing a conformational change that exposes myosin-binding sites on actin.
What happens when ATP binds to the myosin head?
The myosin head detaches from the actin, leading to muscle relaxation.
What is the purpose of creatine phosphate during muscle contraction?
Creatine phosphate provides a rapid source of energy by regenerating ATP from ADP during the initial stages of contraction.
What are the four main events of excitation-contraction coupling?
1) ACh release from the somatic motor neuron 2) Action potential in the muscle fiber 3) Ca2+ release from the SR 4) Ca2+ binding to TnC to initiate contraction.
How does anaerobic cellular respiration contribute to ATP production?
It generates ATP from glucose without oxygen, producing lactic acid in the process.
What are the products of aerobic cellular respiration in muscle fibers?
36 molecules of ATP, CO2, H2O, and heat.
What occurs during oxygen debt after intense exercise?
Additional oxygen is taken in to convert lactic acid back to glycogen, resynthesize phosphocreatine, and replenish oxygen stores.
What is rigor mortis in relation to muscle contraction?
It is the contracted state of muscle that occurs when ATP is depleted, preventing myosin from detaching from actin.