Psy 201 Ch 3 Set A: The Neuron

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Psy 201 Ch 3 Set A: The Neuron
2014-02-25 21:14:18

Exam 2
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  1. What approach studies cells in the body?
    biological - Behavioral Neuroscience; mind and body connection; nervous and endocrine systems; Area of specialization: behavioral neuroscience and physiological/biological perspective
  2. Cells in the body
    receptor cells (neural receptors); neurons; effector cells; glial cells
  3. receptor cells (neural receptors)
    located in the sense organs; receive stimulation
  4. neurons
    transport or transmit messages; located between receptor and effector cells
  5. effector cells
    located near the muscles and glands; tell muscles to contract and glands to secrete
  6. glial cells
    do not send or receive nerve impulses; hold neurons in place; absorb toxins and waste materials that would damage or kill neurons; outnumber neurons about 10 to 1
  7. The Neuron
    basic building block of the nervous system; main role is transmit/transport messages; single nerve cell; 100 billion nerve cells; brain and spinal cord; various shapes and sizes; must use microscope; bundle of neurons - nerve; supported by glial (glue) cells
  8. 3 types of neurons
    sensory (afferent); interneurons; motor (efferent)
  9. sensory (afferent) neuron
    transmit messages from receptor cells in sense organs to CNS
  10. interneurons
    also called association neurons; connect one neuron to another; most located in CNS
  11. motor (efferent) neurons
    transmit messages from the CNS to effector cells near the muscles and glands; muscles contract, glands secrete
  12. Central Nervous System (CNS)
    the brain and spinal cord
  13. Structure of the neuron
    all neurons have three main parts: dendrites, soma (cell body), and axon; other parts: myelin sheath, nodes, axonal terminals, terminal buttons, synaptic vesicles, and synaptic cleft
  14. dendrites
    short fibers; collect messages from neighboring neurons
  15. soma (cell body)
    carry out the basic functions of cell; nucleus is located here
  16. axon
    long fiber; message leaves neuron by way of axon; additional structures of neurons
  17. myelin sheath
    fatty, white substance; surrounds axon; helps message travel down axon; speeds up the impulse
  18. nodes (nodes of ranvier)
    breaks in the myelin sheath; impulse jumps from node to node
  19. axonal terminals
    end of axon; axon splits into many parts; terminals connect to other neurons
  20. terminal buttons
    knobs at the end of terminal; house synaptic vesicles
  21. synaptic vesicles
    tiny oval sacs; holds the neurotransmitters
  22. synaptic cleft
    gap; space between two neurons
  23. Neural Impulse
    communication between neurons; message is being conducted; neurons do not touch physically; communication is electrochemical in nature; is like a tiny battery
  24. ions
    electrically charged particles/atoms (positive or negative)
  25. state/potential of neuron
    two states: resting state/potential and acting state/potential; distinction: stimulation/impulse, membrane, ions
  26. resting potential
    no stimulation (not receiving any messages); no impuse; membrane is semi-permeable; cell is more negatively charged inside than outside; condition of cell is polarized
  27. semi-permeable
    allows some ions to come in while holding others outside
  28. action potential
    cell is stimulated; neuron has "fired" impulse or message; membrane is permeable; channels open up, more ions flow in; changes condition of cell: depolarized
  29. Refractory Periods
    after firing, cell must rest/recover; two refractory periods: absolute and relative
  30. Absolute Refractory Period
    immediately following action potential; membrane is not excitable; cannot discharge another impuse
  31. Relative Refractory Period
    immediately following the absolute refractory period; membrane is excitable; impulse must be stronger than the initial impulse (stimulation)
  32. All or None Law
    action potentials occur either at a uniform and maximum intensity or they do not occur at all
  33. Cell Chemical Communication
    Two types of chemical reactions can occur (neurotransmitters released): excitatory or inhibitory
  34. excitatory
    causes the action potential; neuron fires
  35. inhibitory
    prevents the neuron from firing; each neurotransmitter fits like a lock and key; deactivation must occur, two ways: enzymes and reputake
  36. enzymes
    neurotransmitters can be broken down by other chemicals
  37. reuptake
    transmitter molecules are taken back into the presynaptic axon terminals