Chapter 46 Animal Sensory Systems and Movement

  1. Pheromone
    signal b/w individuals that causes a change in behavior or physiology
  2. How can animals sense a change in the environment?
    • 1. transduction - conversion of external stimulus to an internal signal through action potential
    • 2. amplification of signal
    • 3. transmit to central nervous system
    • 4. integration - processing with other signals
  3. nociceptors
    sense danger/harmful stimuli
  4. thermoreceptors
    sense changes in temp
  5. mechanoreceptors
    sense distortion caused by touch or pressure
  6. chemoreceptors
    perceive different types of molecules
  7. photoreceptors
    sense wavelengths of light
  8. electroreceptors
    sense electric field (only sometimes present)
  9. Electric potential
    • "voltage"
    • created when plasma membrane separates charges
  10. depolarized
    • inside of cell has become more positive
    • in hair cells, causes an inflow of calcium ions, triggering an increase in amount of neurotransmitter released at synapse
  11. hyperpolarized
    cause inside cell to become more negative
  12. How do sensory receptors work?
    They depolarize according to the loudness of the sound (louder the sound, the higher the firing rate of action potentials)
  13. How does the brain distinguish between the different electrical signals?
    • cells highly specific to a certain type of information
    • sensory neurons send their signals to certain parts of the brain only
  14. hearing
    • ability to sense wavelength changes in air pressure
    • depends on # of waves (frequency)
    • different frequencies = pitches
  15. statocyst
    • found in crabs
    • fluid-filled organ with calcium-rich structure that senses pressure due to gravity
  16. How do sensory cells react to pressure?
    • direct phys pressure conforms the ion channel (either making it hyperpolarize or depolarize)
    • leads to new action potential from sensory neuron
  17. stereocilia
    • stiff outgrowths that comprise hair cells
    • when pressure is applied, the stereocilia lean and opens up a pathway for the ions to enter
  18. kinocilium
    • 9+2 arrangement of microtubules
    • part of hair cells
  19. 3 parts of mammalian ear
    • outer ear
    • middle ear
    • inner ear
    • all separated by a membrane
  20. outer ear
    funnels sound into ear canal
Card Set
Chapter 46 Animal Sensory Systems and Movement
Chapter 46 Animal Senses/Mvt (Freeman)