Animal Physiology Key Terms Test 2

  1. Afferent
    Going towards
  2. Centralization
    Tendency of animal groups to concentrate integrative neural functions into a CNS
  3. Cephalization
    The concentration of structures of the nervous system toward the anterior end of the animal
  4. Cerebellar Cortex
    The outer layer of the cerebellum of the vertebrate hindbrain; involved in motor coordination and learning
  5. Cerebral Cortex
    The outer part of the cerebral hemispheres of the vertebrate forebrain; greatly enlarged in birds and mammals
  6. Commissure
    A bundle of axons that connects the two sides of a bilaterally symmetrical central ganglion or bilateral regions of a central nervous system
  7. cranial nerves
    peripheral nerves that connect to the brain
  8. effector
    a tissue, organ, or cell that carries out functions under the direction of the nervous system or another physiological control system
  9. Efferent
    going away
  10. Enteric Division
    One of three divisions of the autonomic nervous system; exerts largely autonomous control over the gut
  11. Entrainment
    The process of synchronizing an endogenous rhythm to an environmental rhythm
  12. Free-running rhythm
    an endogenous rhythm that is not entrained by an environmental rhythm
  13. Gray Matter
    A histological region of a vertebrate central nervous system that contains neuronal cell bodies, dendrites, and synapses as well as axons
  14. Nerve
    A collection of axons running together in the peripheral nervous system
  15. Phasing Factor (Zeitgeber)
    An environmental cue that can entrain a biological clock, synchronizing it to the environmental changes
  16. Photoperiod
    Day length
  17. Somatic Nervous System
    The part of the vertebrate peripheral nervous system that controls skeletal muscles and provides afferent information from sensory receptors not associated with internal organs
  18. Somatotopic Map
    The topographic representation or mapping of the body surface onto a region of the brain
  19. Spinal Nerves
    In a vertebrate, segmental nerves of the peripheral nervous system that attach to the spinal cord
  20. White Matter
    A histologial region of the vertebrate CNS that consists largely of tracts of neuronal axons. The abundance of myelin imparts a glistening white sheen to the tissue
  21. Absolute Refactory Period
    time during and immediately after an action potential in which the voltage threshold is infinite
  22. Action Potential
    brief electrical signal of about 100 mV across the cell membrane of a neuron or other excitable cell that is initiated by a depolarization above threshold and is propagated to the end of an axon or cell
  23. all or none
    not graded.  Occurs fully or not at all
  24. Axon
    a process of a neuron specialized for conveying action potentials away from the body
  25. capacitance
    storage of electrical charge.
  26. cell body
    the portion of the neuron that contains the cell nucleus and is sometimes called the soma or perikaryon
  27. cell theory
    the theory that organisms are composed of cells which act as structural, functional, and developmental units of organization
  28. Conductance
    a measure of how easily electrical current will flow through a conductive pathway
  29. Decremental Spread
    spread of a signal in such a way that signal strength decreases with distance
  30. Depolarization
    a decrease in amplitude of the inside-negative electrical potential of a cell membrane toward zero. Any increase in the inside positivity of a cell membrane even if it exceeds zero
  31. Electrogenic Pump
    an active transport process that pumps net charge across a membrane, acting to generate an electric current across the membrane and to produce a voltage difference across the membrane
  32. Electroneutral Pump
    an active transport process that pumps charges across a membrane such that no difference of charge is created across the membrane
  33. Equilibrium Potential
    the membrane potential at which an ion species is at electrochemical equilibrium
  34. Excitable Cells
    cells that can generate action potentials because their cell membranes contain voltage-gated channels
  35. Glial Cells (Neuroglia)
    Cells in an animals neural tissues that are considered support cells. the may play secondary roles in signaling and integration
  36. Goldman Equation
    an equation that describes membrane potential in terms of the concentrations of and membrane permeabilities to more than one ion species
  37. Graded Potential
    A voltage channel that is variable in amplitude
  38. Hodgkin Cycle
    • the cycle that explains the rising phase of an action potential
    • Depolarization opens VG-Na+ channels which results in further depolarization and the opening of more Na+ channels
  39. Hormone
    • A chemical substance that is released by nonneural endocrine cells or by neurons that is carried to distant target cells where it exerts regulatory influences on their function¬†
    • 3 major classes: steroids, peptides or proteins, and amines
  40. Hyperpolarization
    A voltage change that makes a cell membrane potential more inside-negative
  41. Innervate
    provide neural input
  42. Integration
    harmonious control of output and refers to the integration of signals
  43. Myelin
    An insulating sheath around an axon composed of glial cells that increases the velocity of the propagation of action potentials
  44. Nernst Equation
    equation that is used to determine the equilibrium electrical potential for a given ion when given its concentration on both sides of the membrane
  45. Neuron Doctrine
    the theory that the nervous system is composed of discrete cellular elements that are its fundamental signaling elements
  46. Neuron
    a nerve cell
  47. Neurotransmitter
    a molecule that is used as a chemical signal in synaptic transmission
  48. Optogenetics
    light-gated ion channels are express in neuronal membranes of animals and then light signals can be used to modulate the membrane potential of the neuronal membranes
  49. Passive Electrical Properties
    The electrical properties of a cell that do not involve a change in membrane ion permeability
  50. Patch-clamp Recording
    a method of measuring single-channel currents by sealing a glass capillary microelectrode to a patch of cell membrane
  51. Reflex
    A simple, relatively stereotyped, but graded behavioral response to a specific stimulus
  52. Relative Refractory Period
    brief period following an action potential during which the voltage threshold is elevated and is therefore difficult, but not impossible to generate another action potential
  53. Resistance
    inhibition of electric current
  54. Saltatory Conduction
    Propagation of action potentials in a spatially discontinuous manner along a myelinated axon by jumping from one node of Ranvier to another
  55. Voltage Clamp
    An experimental method to measure ionic current flow by imposing a selected membrane potential on a cell and monitoring the exogenously applied current necessary to maintain the potential
  56. Voltage Threshold
    The critical value of membrane depolarization that is just enough to trigger an action potential
  57. Voltage
    A measure of potential energy present because of charge separation
Card Set
Animal Physiology Key Terms Test 2
Key Terms from the Textbook