BIOL 404-Exam 4-Muscle 2

  1. What is the Sarcoplasmic reticulum analogous to?
    The endoplasmic reticulum
  2. What is the main purpose of the sarcoplasmic reticulum?
    To store Calcium
  3. How are the T-tubules and sarcoplasmic reticulum connected?
    By junctions composed of two integral membrane proteins
  4. What is the integral membrane protein in the T-tubule that comprises half of its junction with the sarcoplasmic reticulum?
    Dihydropyridine (DHP)
  5. What is Dihydropyridine?
    An integral membrane protein of the T-tubule that forms a junction with the sarcoplasmic reticulum
  6. What type of membrane protein is DHP?
    voltage sensitive Ca Channel
  7. What is the name of the voltage sensitive Ca Channel in the T-tubule membrane?
    DHP = dihydropyridine
  8. What is a motor unit?
    A motor neuron + The skeletal muscle it innervates
  9. How many motor neurons innervate each muscle fiber?
  10. How many muscle fibers are innervated by one motor neuron?
  11. Within a whole muscle how many motor neurons are there?
  12. What is the only mechanism by which action potentials are initiated in skeletal muscle?
    Stimulation by a nerve fiber
  13. What are the two terms for a nerve cells whose axons innervate skeletal muscle?
    • Motor neuron
    • Somatic efferent neuron
  14. Where are the cell bodies of somatic efferent neurons (motor neurons) located?
    Brain stem or spinal cord
  15. Describe the general morphology of the motor neurons?
    • Cell bodies in the brainstem or spinal cord
    • Myelinated
    • Largest diameter axons
    • high velocity propogation
  16. What are distinct characteristics of a motor neuron axon?
    • Widest diameter
    • myelinated
    • High velocity conduction
  17. Where are neurotransmitters located prior to release in motor neurons?
  18. Where are neurotransmitters located prior to release in neurons of the nervous system?
  19. What neurotransmitter is found at the neuromuscular junction in motor neurons?
  20. What is the term for the muscle fiber plasma membrane that lies at the neuromuscular junction?
    The Motor end plate
  21. What is the motor end plate?
    The muscle fiber plasma membrane at the neuromuscular junction
  22. What is the junction of the axon terminal and a motor endplate called?
    The neuromuscular junction
  23. What is a neuromuscular junction?
    The junction between the axon terminal and the motor end plate
Card Set
BIOL 404-Exam 4-Muscle 2
BIOL 404-Exam 4-Muscle 2