Neurons and synapses

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Neurons and synapses
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Organization of the Nervous System

• Central nervous system (CNS)
• Brain
• Spinal cord
• Peripheral
• nerves

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Sensory and motor neurons

• Sensory neurons
• Carry nerve impulses from to the CNS
• Motor neurons
• Carry impulses from the CNS to effectors
• effectors (muscle and gland cells)
• Relay neurons
• Carry impulses within the CNS
• between neurons

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Structure of a motor neuron
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Synapses

• Synapse- Junction between two
• neurons
• Messages are passed
• across the synapse in
• the form of chemicals
• - Neurotransmitters

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Stages in synaptic transmission
http//www.youtube.com/watch?vz3F5dfmQ3hk http//
www.youtube.com/watch?v9nUY6o-LCWY
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Vocabulary

• Central nervous system (CNS) part of nervous
  system that consists of the brain and spinal
  cord, regulating the bodys responses to external
  and internal stimuli
• Neurons cells in the central nervous system that
  can carry messages at high speed in the form of
  electrical impulses.
• Spinal cord a long, thin, tubular bundle of
  nervous tissue and support cells that extends
  from the brain
• Peripheral nerves nerves that connect all parts
  of the body to the central nervous sytem
• Sensory neurons neurons that carry nerve
  impulses from sensory cells (receptors) to the
  CNS
• Motor neurons neurons that carry impulses from
  the CNS to effectors (muscle and gland cells)

• Relay neurons neurons that carry impulses within
  the CNS, from one neuron to another
• Axon a long, slender projection of a neuron that
  conducts electrical impulses away from the
  neurons cell body (soma)
• Dendrites the branched projections of a neuron
  that act to conduct the electrochemical
  stimulation received from other neural cells to
  soma
• Neurotransmitters endogenous chemicals which
  transmit signals from a neuron to a target cell
  across a synapse
• Depolarization a change in cells membrane
  potential, making it more positive, or less
  negative
• Vesicles a small membrane-enclosed sac that can
  store or transport susbstances