Eyes & Vision
The layers of the eye wall and their functions
Fibrous layer: When touched, blinking and increases tear production occur & provides shape to the eye
Vascular layer: choroid region prevents light from scattering in the eye, iris-regulates the amount of light entering the eye
Sensory layer: retina prevents light from scattering in the eye and acts as phagocytes to remove dead or damaged receptor cells and restore vitamin A needed for vision
what receptors respond to physical forces?
mechanoreceptors
The taste sensations
Sweet receptors, sour receptors, Umami, Bitter, and Salty
describe ophthalmoscopic examination
To detect pathological conditions like diabetes, arteriosclerosis, and degeneration of the optic nerve and the retina
Male
An area in our eye called the optic disc where there are no photo receptors results in a blind spot.
When light from an object is focused on the optic disk, the object disappears from our view.
What are the names of the auditory ossicles?
malleus (hammer), incus (anvil), stapes (stirrup)
Where is the odor snapshot made?
In the olfactory cortex
presbyopia begins at what age
40
Explain conduction and sensorineural deafness
· Conduction deafness: When something interferes with the conduction of sound vibrations to the fluids of the inner ear
· Sensorineural deafness: When there is degermation or damage to the receptor cells in the spiral organ of Corti, cochlear nerve, or the neurons of the auditory cortex
Convergence and pupillary reflexes
Photopupillary reflexes are when the eye constricts to a bright light. This protects the eye.
Convergence is a reflexive movement of the eyes medially when we view close objects, both eye eye are aimed at the object being viewed.
List the functions of the external, middle, and internal ear
External: composed of auricle and external acoustic meatus. Its ceruminous glands secrete earwax
· Middle: malleus, incus, stapes. These bones transmit vibratory motion of the eardrum to the fluids of the inner ear.
· Inner: bony labyrinth and membranous labyrinth. Transforms vibrations into electrical impulses.
What modifies taste
Dorsal tongue, papillae
What are cataracts
loss of lens transparency
List the eye accessories and what they do
Eyelids: cover the corners of the eye, Palpebral fissure: space between the eyelids when the eyes are open, Conjunctiva: covers outer surface of the eyeball, Lacrimal caruncle: produce an oily secretion that lubricates the eye, Lacrimal apparatus: consists of ducts that drain secretions into nasal cavity, Lacrimal glands: release a dilute salt solution through several small ducts, Ciliary glands: ducts open at eyelash follicles, Tarsal glands: modified sebaceous glands, Eyelashes: protrude out of the eye
what is the name of the inflammation of the middle ear?
otitis media
describe the visual pathway to the visual cortex
Axons carrying impulses from retina are bundled at the back of the eye and leave the back of the eye as the optic nerve. At the optic chiasma, each eye's fibers cross over to the opposite side of the brain. The optic tracts synapse with neurons in the thalamus whose axons form optic radiation that runs to the occipital lobe of the brain. They then synapse with the cortical cells, then sight occur