Photoreception Accessory Structures Eyebrows Eyelids Lacrimal caruncle Sebaceous & sweat glands; Sandman’s eye sand. Epicanthic fold Eyelashes Innervated with many nerves. Conjuctiva—transparent membrane—over eyelids and sclera. Important in lubrication of the eye.
Sebaceous & sweat glands; Sandman’s eye sand. Epicanthic fold
Innervated with many nerves.
Conjuctiva—transparent membrane—over eyelids and sclera. Important in lubrication of the eye.
Tears contain antibodies and lysozyme.The Eye
Strabismus—”cross-eyed” Affected eye rotates either medially or laterally. Treatments and effects.
Glaucoma—excessive aqueous humor—Intraocular pressure.
Cataract—clouding of the lens. May be caused by sunlight, diabetes, smoking, vitamin deficiencies,, etc…
Night blindnessEye Disorders
Outer, middle, and inner ear
Pinna or auricle
Are bigger ears better?
External auditory canal
How does this structure function?
Malleus, incus, stapes
Malleus is attached to the eardrum.
Stapes is attached to the oval window of the inner ear.
Inside the bony labyrinth
Filled with fluid
Vestibule—oval window is attached to this structure.
Contains equilibrium receptors.
Semicircular canals—poster and lateral to the vestibule. Ampulla—equilibrium receptors.Hearing
Organ of Corti
Auditory cortex in temporal lobes
Disorders of the Ear
Otosclerosis—stapes becomes fused to oval window.
Sensorineural deafness—damage to hair cells or neural pathways.
Inputs from the inner ear, eyes, and stretch receptors
Semicircular canals—dynamic equilibrium
Maculae—respond to straight line changes in speed and direction, not to rotation
Respond only to changes in velocity or acceleration.Equilibrium
Most on the tongue
Papillae—projections of the surface of the tongue.
Gustatory and taste cells—taste receptors
Replaced every 7 to 10 days—taste buds
4 basic tastes
Sweet, salty, bitter, sour
Sweet—sugars, alcohols, amino acids
Olfactory epithelium in the roof of the nasal cavity.
Olfactory receptor cells
Life span of 60 days.
Olfactory receptors to:
Olfactory nerves to:
Olfactory bulbs to:
Olfactory tract to:
Thalamus to the olfactory cortex and the frontal lobe and to the hypothalamus, amygdala, and other parts of the limbic system.