Nervous Tissue the neuron

  1. Where does nervous tissue develop from?
    embryonic neural tube & neuro crest
  2. What are the two type of cells that form nervous tissue?
    neurons & glial cells (supporting cells)
  3. Neuron
    • excitable
    • can send an impulse (electrical signal)
    • three major parts - cell body, dendrites, axon
    • cells live for many years
    • do not undergo mitosis
    • highly dependant on oxygen due to high metabolic rate
  4. Dendrites
    receptive ends allowing signals to travel towards cell body
  5. Axons
    extend out of one side of cell body called axon hillock
  6. Collateral axons
    resut when axons branch
  7. Terminal branches
    multiple branches at the end of an axon
  8. Terminal axons
    end in knobs
  9. schwann cells
    where the length of axon is surrounded by
  10. Both the schawnn cells and length of axon surrounding these cells together make up what?
    myelin sheath
  11. Node of ranvier
    a gap between each schawnn cell
  12. Synapses
    connecting allowing one neuron to communicate with the next
  13. axodendritic synapse
    axon makes synapse with dendrite
  14. axosomatic synapse
    axon connects with cell body of another neuron
  15. axoaxonic synapses
    synapse exists between two axons
  16. presynaptic and postsynaptic neuron
    presynaptic neuron - cell conducting impulse towards synapse

    postsynaptic neuron - recieves impulse & sends it away from synapse
  17. neurotransmitter
    chemical substance allowing impulse to jump from neuron to neuron
  18. synaptic vesicles
    membrane bound sacs containing neurotransmitter
  19. synaptic cleft
    gap seperating plasma membrane of two neurons
  20. Impulse
    electrical signal sent down plasma membrane of neuron
  21. Resting potential, action potential, graded potential, synaptic potential
    RP: neuron not sending any type of impulse

    AP: impulse travels down axons and as it leaves, axon returns to resting potential

    GP: travels toward axon hillock & initiates impulse

    • SP
    • - excitatory synapse- changes potential so postsynaptic neuron can send impulse
    • - inhibitory synapse - stops travel of an impulse
  22. sensory neuron (afferent)
    neurons that have receptors in PNS & send signals toward CNS
  23. Receptors
    cells capturing stimulus & transfer signal onto dendrite of sensory neuron with the dendrite connecting to cell body sending axon into CNS (spinal cord)
  24. Motor neuron (efferent)
    multipolar neurons with cell bodies in CNS & connect in body to effector cells (muscles/glands)
  25. effector cells
  26. Interneuron (association)
    multipolar neurons in CNS linking sensory & motor neurons relaying messages to & from brain & process information
  27. What neurons are afferent, efferent, & association?
    • sensory neuron - afferent
    • interneuron - association
    • motor neuron - efferent
Card Set
Nervous Tissue the neuron
nervous tissue the neuron