Nervous and Endocrine System

  1. Nervous System
    one of the smallest systems, but most complex

    it depends on electrical activity
  2. Nervous and Endocrine Systems
    Control and adjust activities of other systems.

    Use Chemical communication

    Nervous System - rapid but brief responses

    Endocrine - slower but often lasts much longer
  3. Functions:
    Sensory Input - mnitoring stimuli occuring inside and outside the body

    Integration - interpetation of sensory input

    Motor output - response to stimuli by activating effector organs
  4. An overview of the Nervous System

    2 anatomoical subdivision
    • CNS Central nervous System
    • *Brain and Spinal Cord
    • *Integrating, processing and coordinating
    • *Intelligence, memory, learning and emotion

    • PNS Peripheral Nervous System
    • *Provides sensory information to the CNS
    • *Carries motor commands to peripheral tissues
  5. Subdivision of the PNS

    The PNS is divided into 2 subdivisons
    The Afferent division of the PNS brings sensory information to the CNS

    The Efferent division carries motor commands to the muscles and glands

    • *The efferent division is divided into 2 subdivisions:
    • **Somatic Nervous Sysgtem (SNS) Skeletal Muscle
    • **Autonomic Nervous System (ANS) Cardiac, Smooth, Glandular
  6. Subdivisions - Continued
    The efferent division begins inside the CNS and ends at the Effector
  7. The Autonomic Nervous System is further divided into the
    • Sympathetic - Fight Fight Fight
    • *Activated during exercise, excitement, and emergencies

    • Parasympathetic rest and digest
    • *Concerned with conserving energy
  8. Cellular Organization in Neural Tissue

    Neural tissue contains two distinct cell types
    Neurons: responsible for the transfer and the processing of information in the nervous system

    Neueoglia: Support Cells
  9. Neuroglia
    • Neuroglia have many functions including:
    • *providing the framework for the neural tissue
    • *maintaining the intercellular environment of the neuron
    • *Act as phagocytes (protection)

    • 100 billion neuroglia or glial cells
    • *roughly 5 tines the number of neurons

    • Types
    • *CNS
    • **Astrocytes
    • Microglia
    • Ependeymal Cells
    • Oligodendrocytes

    • PNS
    • *Satellite Cells
    • *Schwan Cells
  10. Astrocytes
    Are the largest and the most numerous glial cells.

    • Have a variety of functions:
    • Maintaining the blood brain barrier
    • Creating a three dimensional framework for the CNS
    • Performing repairs in damaged neural tissue
    • Guiding neuron development
    • Controlling the intersitial enviorinment
  11. Microglia and Ependymal
    Produce the CSF
  12. Oligodendrocytes
    • Produce a myelin sheath in the axons (insulating sheath)
    • Creates a faster impulse conduction along the axon

    Nodes of Ravier is the jumping action called saltatory from node to node
  13. Neuroglia of the PNS
    Satellite Cells - are found in assoc. of the cell body of the neurons

    Regulates nutrients for the body
  14. Neuroglia of the PNS

    Schwann Cells
    Counterpart to the oligodendrocytes

    Peripherial Cells
  15. CNS Spinal Cord
    White Matter = myelinated axons (lighter in appearance)

    Grey Matter = non myelinated axons, cell bodies, and dendrites (Darker in Appearance)
  16. Pseudounipolar Neuron
    the cellbody is more in the center of the extension away from the tree portion.

    Brings in Sensory information
  17. Neuron Calssification Functional:
    3 types

    • *Sensory Neuron
    • **Send Nerve impulses from a sense organ (receptor) to the CNS

    • *Interneuron
    • **Contained within the CNS
    • **Receives Impulses form the Sensory Neurons and/or Interneurons

    • *Motor Neuron
    • **Sends nerve impulses away from the CNS to an Effector
  18. Nervous Tissue
    Bundles of Axons in the PNS = Nerves

    Bundles of Axons in the CNS = Tracts

    Collection of the cell bodies in PNS = Ganglia
  19. Transmission of a Nerve Impulse

    What Exactly is an "Impulse"
    Na+ ion movement across a membrane

    polarity change of membrane surface (transmembrane potential)

    Travels along the membrane surface like a "Domino Effect"
  20. Saltatory Conduction
    Current passes through a myelinated axon only at the nodes of Ranvier

    Voltage gated Na+ channels are concentrated at these nodes

    Action potentials are triggered only at the nodes and jump from one node to the next

    much faster than conduction along unmyelinated axons
Author
MeanEddieG
ID
138286
Card Set
Nervous and Endocrine System
Description
Nervous System
Updated