Ch 10 Nervous System

• what makes up the central nervous system

  brain and spinal cord
• what makes up the peripheral nervous system

  cranial nerves, spinal nerves, plexuses, peripheral nerves throughout the body
• what do cranial and spinal nerves do

  sensory - carry message to brain

  motor - carry message from the brain

  mixed - have sensory and motor fibers
• autonomic nervous system subdivisions

  carries impulses from the central nervous system to the organs

  sympathetic - nerves stimulate the body under stress

  parasympathetic - nerve balance the sympathetic system

  • slow heart rate
  • lower blood pressure
• what are neurons made of

  dendrite, cell nucleus, axon (myelin sheath and neurilemma)

  terminal end fibers (secrete neurotransmitters)

  neurotransmitters transfer impulse across synapse
• what are ganglia

  small clusters of nerve cell bodies in PNS
• what do glia cells do

  maintain the health of the nervous system and DO NOT transmit impulses
• astrocytes

  star shaped that transport water and salts
• microglia

  small cells with dendrites that protect neurons in response to inflammation
• oligodendroglia

  have few dendrites and form myelin sheath
• ependymal cells

  line membranes in brain and spinal cord where CSF is produced
• characteristics of cerebrum

  largest section of the brain.

  surface nerve cells are cerebral cortex

  manages speech, vision, smell, movement, hearing, and thought
• cerebellum characteristics

  coordinates voluntary movements

  maintains balance
• thalamus function

  integrates and monitors impulses from skin (pain)
• function of the hypothalamus

  controls body temp, sleep, appetite, sexual desire, and emotions

  regulates release of hormones from the pituitary gland

  monitor sympathetic and parasympathetic nervous system
• pons

  bridges the cerebrum and cerebellum with the rest of the brain

  houses nerves for face and eyes
• medulla oblongata

  connects the spinal cord to the brain

  nerve tracts from side to side

  regulates BV, heart, and respiratory system
• acetylcholine

  neurotransmitter chemical released at ends of nerve cells
• afferent nerve

  carries messages toward the brain and spinal cord
• arachnoid membrane

  middle layer of the three membrane that surround the brain and spinal cord
• autonomic nervous system

  nerves that control involuntary body functions of muscles, glands, and internal organs
• axon

  microscopic fiber that carries the nervous impulse along a nerve cell
• blood brain barrier

  protective separation between the blood and brain that keeps substances from penetrating capillary walls and entering the brain
• brainstem

  posterior portion of the brain that connects the cerebrum with the spinal cord
• cauda equina

  collection of spinal nerves below the end of the spinal cord
• cell body

  the part of a nerve cell that contains the nucleus
• cranial nerves

  twelve pairs; carry message to and from the brain with regard to the head and neck (except vagus nerve)
• dendrite

  microscopic branching fiber of a nerve cell, the first part to receive the nervous impulse
• dura mater

  thick and outermost layer of the meninges surrounding and protecting the brain and spinal cord
• efferent nerve

  carries message away from the brain and spinal cord, motor nerve
• ependymal cell

  glial cells that lines the membrane within the brain and spinal cord, helps form CSF
• ganglion

  collection of nerve cell bodies in the peripheral nervous system
• gyrus

  sheet of nerve cells that produces a rounded ridge on the surface of the cerebral cortex, convolution
• meninges

  three protective membranes that surround the brain and spinal cord
• microglial cells

  phagocytic glial cell that removes waste products from the central nervous system
• motor nerve

  carries messages away from the brain and spinal cord to muscles and organs, efferent nerve
• myelin sheath

  covering of white fatty tissue that surrounds and insulates the axon of a nerve cell, speeds impulse conduction
• nerve

  macroscopic cord like collection of fibers (axons and dendrites) that carry electrical impulses
• pia mater

  the thin and delicate inner membrane of the meninges
• plexus

  large interlacing network of nerves