Biomedical Core

  1. The condition of perfect focus is called
  2. If the lens and cornea focus the image internal to the retina, the condition is called
  3. If the image is focused external to the retina, the condition is called
  4. Normally, light rays pass first through ______ and are ____ by the lens, this focuses an image on the _______ surface.
    cornea; bent (refracted); receptor
  5. Lower energy =
    longer wavelength

    *radio waves, microwaves
  6. Visible spectrum
    color corresponds to wavelength
  7. Higher energy =
    shorter wavelength

    *Ultraviolet, x-rays, Gamma rays
  8. Wavelength corresponds to
    hue or color
  9. The distance between the crest and trough of the wave is the
  10. Amplitude corresponds to the
    brightness of the light
  11. Rods are
    specialized to code for the presence or absence of light.

    rods can detect as few as 1-3 photons
  12. Cones are
    specialized to code for color information

    color = wavelength of light
  13. Light changes shape of
  14. Retinal is made from
    Vitamin A
  15. Retinal + opsin =
    rhodopsin, the visual transducer in rods
  16. Transduction causes changes in rods
    -In darkness, open Na+ channels keep rod depolarized (more+)

    -Glutamate is the neurotransmitter; more glutamate is released in the dark

    -Photons cause Na+ channels to close

    -This hyperpolarizes the rod

    -Glutamate release is turned off in the light

    -Weird: when your eyes are closed and you are asleep is when rods are the most active
  17. Therefore, axons from the left nasal retina and right temporal retina, which carry information from the left half of the world, join together at the _____ ______ and form the right _____ _____. The right optic tract ends in the right side of the thalamus. The right thalamus then sends axons through the right _____ ________ to the right ______ _______ in the occipital lobe.
    optic chiasm; optic tract; optic radiations; visual cortex
  18. Olfaction is the sense of
  19. Olfactory receptors found on
    superior surface of sinuses (superior nasal concha)
  20. Olfactory receptor surface in humans about the size of a
    postage stamp
  21. Odorants are
    small molecules, carried by air, that are dissolved in the mucus layer that covers the olfactory epithelium.
  22. Olfactory Transduction:
    -Odorant molecule binds to receptor protein.

    -This activates a G protein pathway.

    - Second messenger opens a Na+ channel
  23. After the olfactory stimulus is analyzed by the cells of the ________ _________, the processed signal is passed via the _______ _____ through the _______ ______ of the skull to the ________ bulb which lies along the ventral surface of the frontal lobe. There, the signal is processed further, and is transferred via the _______ _____ to the _______ ______ in the temporal lobe.
    olfactory epithelium; olfactory nerve; ethmoid bone; olfactory; olfactory tract; olfactory cortex
  24. The delicate nerve axons which pass through the cribriform plate of the ethmoid bone are easily torn by head trauma. When this happens, the patient permanently loses the sense of smell, a condition called
  25. Smells have direct access to the emotional centers of
    the brain, which is why an old friend's cologne can trigger a strong emotional response.
  26. Olfactory pathway is the only sensory pathway that is not relayed through the
Card Set
Biomedical Core
Objective 21-27