1. What is the functional unit of the nervous system?
  2. What else is the cell body known as?
  3. What two cells produce myelin and where are they located?
    • Oligodendrocytes in the CNS
    • Schwann cells in the PNS
  4. What are the gaps between the myelin sheaths called?
    nodes of Ranvier
  5. What is the typical resting membrane potential?
    -70 millivolts
  6. Is the concentration of K+ higher inside or outside the neuron?
  7. The Na/K pump has what ratio?
    3 Na out for every 2 K in
  8. How is an action potential generated?
    depolarization of a cell
  9. Which voltage gated channel opens in response to depolarization?
    Na followed by K
  10. What factors contribute the the speed of an action potential?
    • mylenation
    • diameter of the axon
  11. What are effector cells?
    Neurons that communicate with cells in muscles or glands rather than another neuron
  12. When an action potential reaches the end of the axon, what is released into the synapse?
  13. How are neurotransmitters removed from the synapse?
    • by a protein
    • degraded by enzymes (acetylcholinesterase inactivates acetylcholine)
    • diffusion out of the synapse
  14. Which type of invertebrate does not have an organized nervous system?
  15. Which type of invertebrate uses a nerve net?
  16. What are the three types of neurons in the vertebrate system?
    • sensory (afferent)
    • motor (efferent)
    • interneurons
  17. What are bundles of axons called?
  18. What is a network of nerve fibers called?
    a plexus
  19. What is a cluster of neuronal cell bodies called?
    • Ganglia in periphery
    • Nuclei in the CNS
  20. What is the forebrain also known as?
    Presencephalon, which consists of the telencephalon and the diencephalon
  21. What is the midbrain also know as?
    Mesencephalon, which is a relay center for visual and auditory impulses
  22. What is the hindbrain also known as?
    Rhombencephalon, which consists of the cerebellum, the pons, and the medulla oblongata
  23. How does sensory information enter/exit the spinal cord?
    Through the dorsal horn/ventral horn
  24. What are the two divisions of the PNS?
    • somatic: voluntary movement
    • autonomic: involuntary movement
  25. What is the white of the eye called?
    the sclera
  26. What helps supply the retina with blood
    choroid layer
  27. Cones can absorb what three colors?
    red, green, and blue
  28. What jellylike liquid fills the eye?
    Vitreous humor
  29. What is nearsightedness?
    Myopia: image focused in front of the retina
  30. What is farsightedness?
    hyperopia: image is focused behind the retina
  31. What are the three bones in the ear and what are they known as?
    • known as ossicles
    • malleus
    • incus
    • stapes
Card Set
Biology DAT 7