quiz #1- action potentials

  1. What is the resting potential of a cell?
    roughly -70mV
  2. What are the four components of a neuron?
    • dendrites: receiving prongs
    • axon: reduces from cell body to target cell
    • Presynaptic terminal: fingerlike projections that are transmitting elements
    • soma: where neurotransmitters are produced
  3. Where is K+ concentration the greatest?
    in the cell
  4. Where is Na+ concentration the greatest?
    out of the cell
  5. What is the permeability of a membrane (in terms of high or low for potassium or sodium)?
    • high for potassium
    • low for sodium
  6. What is K+ equilibrium potential?
    -120 mV
  7. What is Na+ equilibrium potential?
    +35 mV
  8. What is depolarization?
    lose - charge
  9. What is repolarization?
    Try to get back to -70
  10. What is hyperpolarization?
    increase - charge
  11. What is threshold?
    -55 mV
  12. What does the Na/K pump do?
    • reestablish the concentration
    • Na OUT of cell
    • K IN cell
  13. What is quantal release?
    each synapse releases a set quantity of neurotransmitters
  14. How is a neurotransmitter released?
    Presynaptic neuron releases a neurotransmitter into the synaptic cleft and the neurotransmitter diffuses from 1 side to another then binds to post synaptic neuron.
  15. What is myasthenia gravis?
    receptors for Ach blocked at neurotransmitter junction so the muscles don't contract
  16. What is a cause of depression?
    decreased serotonin produced in the brain
  17. Where is Acetylcholine produced?
    • neuromuscular junction
    • basal ganglia
    • parasympatheric post-ganglionic neurons
  18. Where is dopamine produced?
    substantia nigra
  19. Where is norepinephrine produced?
    • brain stem
    • sympathetic post-ganglionic cells
  20. Where is serotonin produced?
  21. Where is glycine produced?
    spinal cord- inhibitory
  22. Where is GABA (gamma aminobutyric acid) produced:
    spinal cord- inhibitory
  23. Where is Glutamate produced?
    widespread- inhibitory
  24. What is one ion that can cause an inhibitory post-synaptic potential
    K+: causes hyperpolarization
  25. What is one ion that can cause an excitatory post-synaptic potential?
    Na+- causes depolarization
  26. What is temporal summation?
    • combined effect of series of small potential changes causes depolarizations
    • frequency of action potentials
  27. What is spatial summation?
    • receptors or synaptic potentials in different regions added together to cause depolarization
    • number of fibers processing action potentials
  28. TRUE OR FALSE: EPSP-IPSP cancellation can NOT occur.
  29. What are two things that can make an action potential occur faster?
    • axon diamter (more can get through at once)
    • myelination (prevents leakage)
  30. What is saltatory conduction?
    when an action potential proceedes down the myelinated axon jumping from node to node
Card Set
quiz #1- action potentials
action potentials, membrane potential, IPSP, EPSP