What is the most outer covering (made up of areolar connective tissue sheath) of a muscle fiber called?     endomysium     perimysium     epimysium     sarcolemma What do synaptic vesicles of a neuromuscular junction contain?     sodium     serotonin     calcium     acetylcholine

What does it mean to say that a whole muscle respondsto stimuli in a graded fashion? What are the two ways toincrease the force of contraction?

Why will an increase in the strength of a stimulus cause an increase in the force of contraction in a whole muscle but not in a single muscle fiber?

What areas of a muscle cell are the chemically-gated and voltage-gated channels found?

Myofiber,that is mature muscle cells, have more than one nucleus,how does that happen?

How does the structure of the microfilaments allow for linear contraction of a whole muscle cells?

Put these events that occur in skeletal muscle in the correct chronological sequence: 1. Opening of mechanically-gated ryanodine receptors (RyR) on the sarcoplasmic reticulum 2. Ca²+ binding to troponin to initiate contraction 3. Activation of voltage-gated dihydropyridine (DHP) receptor in the T-tubule 4. Na+ influx through ligand-gated ion channels on the motor end plate 4, 3, 2, 1 2, 1, 4, 3 3, 1, 2, 4 4, 3, 1, 2 3, 1, 4, 2

A motor unit from a skeletal muscle contains 1500 muscle fibers. Would this muscle be involved in fine, delicate movements or in powerful, gross movements? Explain.

Which type of muscle fiber uses large amounts of oxygen and has rich supplies of myoglobin? slow oxidative fast oxidative glycolytic fast glycolytic O eccentric

How quickly would skeletal muscle fibers fatigue if they were unable to use oxygen to make ATP? approximately 15 seconds  Approximately 30 seconds  Approximately 60 seconds  Approximately 100 seconds approximately 180 seconds