Sensory Physiology Flashcards
What are the 5 special senses?
- Vision
- Gustation
- Hearing
- Olfaction
- Equilibrium
What are the 5 somatic senses?
- Touch
- Temperature
- Pain
- Itch
- Proprioception
Proprioception
- The ability to sense stimuli arising w/ the body reguarding position, motion, and equilibrium
Sensory receptor cells are distinct cells, mostly found in the ________ of the body.
- Head region
sensory receptor cells are housed in ___________.
- Sensory organs
- ex. Eyes and ears
- Or epithelial structures (taste buds and nose)
sensory receptor cells respond to ________.
- Respond to a stimulus
- sends messages to the brain
What are the types of sensory receptors?
- Mechanoreceptors
- Thermoreceptors
- Photoreceptors
- Chemoreceptors
- Nociceptors
Mechanoreceptors
- respond to mechanical force, such as touch
Thermoreceptors
- Respond to temperature changes
Photoreceptors
- respond to light
Chemoreceptors
- respond to chemicals
Nociceptors
- respond to damaging stimuli such as pain
Stimulus excites a ________.
- receptor (touch excites mechanoreceptors)
the stimulus much be within the receptors ______________.
- Receptive feild (area the receptor monitors)
Stimulus energy gets converted into a graded potential, this is called _________.
- Transduction
- initiates an AP on sensory nerve to CNS
- or causes receptor cell to secrete NT
The sensory cortex is where ___________.
- Where stimuli are counciously interpreted
describe how stimulus of touch is preceived and interpreted.
- Stimulus excites a receptor (touch excites mechano receptor)
- Stimulus must be within the receptors receptive feild
- Stimulus energy gets converted into a graded potential (transduction); an APis initiated on a sensory nerve to the CNS or Causes the receptor cell to secrete NT
- AP is sent to the brain where the stimuli is conciously interpreted in the sensoty cortex
how much of the body’s sensory receptors are found in the eye?
- 70%
the ___________ protects the eye.
- Skull
___________ eye muscles control eye movement. Cranial nerves ___ ___ and ___ control movement. The eye functions similar to a ________.
- 6 extrinsic eye muscles
- cranial nerves 3,4 and 6
- a camera
A) Cornea
B) Pupil
C) Aqueous humor
D) Iris
E) Lens
F) Vitreous humor
G) Sclera
H) Retina
I) Fovea Centralis
J) Optic nerve
K) Optic disc (blind spot)
How does the parasympathetic nervous system effect the eye?
- Pupils become constricted
- Sphincter pupillae muscle contracts
- Pupil size decreases
How does the sympathetic nervous system effect the eye?
- Dilated pupils
- Dilator pupillae muscle contracts
- Pupil size increases
The iris has how many muscles? What are their names?
- The iris has 2 muscles
- Sphincter pupillae
- Dilator pupillae
The retina contains _______.
- photoreceptor cells
- rods and cones
Rod cells
- more numerous
- function in low light
- help see black and white
Cone cells
- Provides high resolution for color vision
- responsible for high acuity (sharpness of vision)
The fovea contains more of what type of cell?
- cones
both rods and cones contain ________.
- Pigments
- Light excites the pigments and we see color
Pathway of information through the eye
- Light in atmosphere
- light hits cornea first
- light travels through aqueous humor where it is refracted
- light then enters pupil
- Light then hits lense and is refracted again
- Light enters vitreous humor in posterior chamber of the eye and is refracted
- Light then hits photoreceptors in the retina
- cones and rods send AP back out towards the optic nerve
- AP reaches the CNS
- information is sent to visual cortex and is processed by the brain
where is the visual cortex located?
- in the posterior portion of the brain
How does the eye work?
- Eye receives light and focuses it on the retina
- Light bends (refracts) when it travels through different mediums
- Air — cornea
- Cornea —- lens
- Lens —- vitreous humor
Glaucoma
- Aqueous humor not draining properly; pressure builds up in the eye
Cataract
- Coulding on the lense (hardening)
Astigmatism
- Abnormally shaped cornea
Color Blindness
- Congenital lack of cone pigments
Gustation and Olfaction sense __________.
- Chemicals
Olfaction
- Smell
Gustation
- Taste
Olfaction anf gustation are both very __________ senses, what does this mean?
- Primative senses
- strong direct connection to most basic needs
- Thirst, hunger, emotion, sex, some forms of memory