special senses

• eye transmits visual stimuli to the brain for interpretation and, in doing so, functions as the organ of vision.
• eyeball is located in the eye orbit, a round, bony hollow formed by several different bones of the skull
• bony orbit and fat cushion protect the eyeball.
• eyelids (upper and lower) are two movable structures composed of skin and two types of muscle: striated and smooth.
• What is a sensation?

  conscious or subconscious awareness of an internal or external stimuli
• These senses include somatic sensations

  (tactile, thermal, pain, and proprioceptive)

  General senses
• These senses are scattered throughout the body

  General Senses
• These senses are simple structures

  General Senses
• These senses includ smell, taste, vision, hearing, and equilibrium

  Special Senses
• These senses are specifically located within the head

  Special Senses
• These senses are anatomically distinct structures


  Special Senses
• These senses form complex neural pathways

  Special Senses
• The process of perceiving smells is known as what?

  Olfaction
• Taste is also known as...


  Gustatory
• Olfactory and gustatory send impulses to what specific part of the body


  The cerebral cortex, then the limbic system
• Which sense is the most strongest of them all?

  Olfaction
• Where is the olfactory epithelium located?

  In the superior (upper) part of the nasal cavity
• What kind of cells does the olfactory epithelium consist of?

  1. olfactory receptors

  2. supporting cells

  3. basal cells
• What type of cells within the olfactory epithelium respond to odor

  olfactory receptors
• What is the function of basal cells within the olfactory epithelium

  They replace the olfactory receptors (stem cells)
• The process of smelling a flower starts a domino effect of events eventually leading to which part of the brain for processing

  Temporal lobe
• Name the subcategories within gustation


  sour, sweet, bitter, salty, & umami
• Where are taste buds located


  tongue, soft palate, pharynx, and larynx
• Taste buds are composed of what type of cells

  Gustatory receptors, which are then surrounded by supporting cells
• What projects from each receptor cell to the surface of the tongue through the taste pore

  A gustatory hair
• On average, what is the lifespan of a gustatory receptor cell

  10 days
• elevations on the tongue which provide a rough texture are known as what

  papillae
• What 3 types of papillae are taste buds found on?


  Vallate papillae- back of tongue

  Fungigorm papillae- entire tongue (scattered)

  Foliate papillae- sides of tongue (only in children)
• Filiform papillae are tactile receptors covering the tongue, but do not contain what

  Taste buds
• What three cranial nerves control the gustatory responses


  Facial (III) Nerve- tip of tongue

  Glossopharyngeal (IX) Nerve- middle/ back of tongue

  Vagus (X) Nerve- throat and epiglottis
• Nerve impluses are eventually propogated till they reach what part of the brain

  Medulla Oblongata
• Vision is possible due to these and the way they perceive light

  photoreceptors
• The accessory structures of the eye include:


  extraocular muscles, palpebra, conjunctiva, and lacrimal glands and ducts.
• What part of the eye allows light to pass into the back of the eye?

  the pupil
• The upper and lower palpebrae are commonly referred to as what

  eyelids
• Name the clear mucous membrane that covers the white part of the eye (avascular)

  Conjunctiva
• where are lacrimal glands located

  superlateral to the eyeball. (upper left/right in coordinance with left/right eye)
• Tears are produced where

  In the lacrimal glands
• What cavity do tears flow into causing nasal stuffiness during crying

  lacrimal puncta
• Watery eyes occur because


  a build up of lacrimal fluid (allergies/inflammation)