The Special Senses Objectives Flashcards
describe and identify the location of olfactory receptors and olfactory epithelium
olfactory epithelium are specialized cells in superior nasal cavity; olfactory receptors are modified bipolar neurons within the epithelium
describe an oderant and how they activate olfactory receptors
odorants are detected by olfactory neurons; odorants are dissolved in mucus surrounding olfactory neuron’s cilia for the activation of olfactory receptors; by attacking the odorant, a sodium channel is opened which leads to an action potential
describe the location and structure of taste buds
taste buds are small clusters of receptor cells and supporting cells scattered about tongue and other surfaces of oral cavity
explain how gustatory receptors are activated
dissolved in saliva
salty and sour = open ion channels which depolarize cell and allow release of neurotransmitter
bitter and sweet and umami = G-protein activation which leads to depolarization by closing Potassium leak channels
describe the 5 primary taste sensations
sweet = simple sugars (glucose, fructose)
sour = hydrogen ions (citric acid)
salty = metal ions (sodium and potassium)
bitter = nitrogen-containing compounds
umami(savory) = glutamate or other amino acids
describe the structure and function of the eye
refer to eye flashcards
describe the retina and location of photoreceptors
retina is the innermost layer of the eyeball and photoreceptors detect and transduce light stimuli into electrical signals (rods and cones)
distinguish between rods and cones
rods = black and white vision in low light levels and also peripheral vision
cones = high-acuity color vision in higher light levels
describe the refraction of light by the cornea and lens
cornea = refractive index close to water
lens = fine tuning and adjustment, change shape
discuss presbyopia, hyperopia, myopia, and astigmatism
presbyopia = near point of accommodation greater than 10-20 inches (corrected with reading glasses)
hyperopia(farsightedness) = eyeball is too short or cornea is too flat; focuses BEHIND retina; blurry vision on close objects (correction with convex lenses or LASIK)
myopia(nearsightedness) = distance between cornea and lens is too great or cornea is too curved; light is focused in FRONT of retina; blurry vision on distant objects (correction with concave lenses or LASIK)
astigmatism = curvature of lens or cornea is irregular; light rays are not evenly refracted; blurry vision at all distances (corrective lenses specialized or LASIK)
describe the structure and function of the inner, middle, and outer ear
refer to ear flashcards
distinguish between static, dynamic, and rotational equilibrium
static = maintaining balance when head is tilted but head and body are not moving
dynamic = maintaining balance when head or body is undergoing rotational or angular motions or linear acceleration
describe the structure and function of a hair cell and how they relate to hearing and equilibrium
refer to ear flashcards and lecture video
describe ways that special senses work together to give a person the “big picture” of what is happening in the world around them
receptors detect and transduce stimuli from various special sensory organs – cranial nerves transmit electrical or neural signals to CNS – neural signals are relayed through thalamus (except olfaction) – awareness occurs in primary sensory cortices – frontal lobe and limbic system integrate special senses into coherent picture of situation – limbic system provides appropriate emotional response and documents associated memories
list the special senses
olfaction - smell
gustation - taste
vision - sight
audition - hearing
vestibular sensation - equilibrium
