Anatomy and Physiology the Unity of Form and Function

Chapter 16 Lens, iris, pupil, cornea, suspensory ligament, ciliary body Posterior eye anatomy Vitreous humor (body), fovea centralis, optic disc, optic nerve, sclera, choroid, retina Anatomical landmarks for the olfactory projection pathways in the brain: Orbitofrontal cortex = this is the area where identification and discrimination of ordors occur Olfactory bulb= these areas are located beneath the frontal lobes Olfactory tract= these travel posteriorly along the underside of the frontal lobes Insula= a mass of cortex deep to the lateral sulcus Amygdala= this structure is immediately rostral to the hippocampus Hippocampus= the memory forming center in the medial temporal lobe Primary olfactory cortex= from here, signals travel into the cerebrum and brainstem Hypothalamus= the inferior portion of the diencephalon Structures of the membranous labyrinth of the ear: Saccule- the most medial portion of the vestibule Utricle- the most lateral portion of the vestibule Ampullae- the expansions at the base of the semicircular ducts Semicircular duct (anterior)- most anterior duct Semicircular duct (lateral)- most lateral duct Semicircular duct (posterior)- most posterior duct Vestibular nerve- serves for equilibrium Cochlear nerve- bundles of axons leading into the cochlea Spiral ganglion of cochlea- innervates the cochlea Cochlear duct- the coiled structure in the inner ear Ear ossicles are tiny bones THE AUDITORY TUBE is a flattened tube which, when opened by actions such as yawning or swallowing, equalizes pressure in the tympanic cavity. Which fluid serves as a cushion between the bony and membranous labyrinths? PERILYMPH Endolymph is located within the membranous labyrinth. The bony labyrinth of the inner ear is lined with a series of fleshy tubes called the MEMBRANOUS LABYRINTH The middle ear is the area between the tympanic membrane (ear drum) and the oval window of the cochlea. Together, the utricle, saccule, and semicircular ducts comprise which of the following? Vestibular apparatus MACULA SACCULI refers to the patch of hair cells and supporting cells positioned vertically on the wall of the saccule Which term refers to patches of sensory epithelium within the utricle and saccule? MACULAE The INNER ear consists of the cochlea and the vestibule which are organs important for the senses of hearing and balance. Structures of the cochlea Cochlear nerve- innervates the cochlea Cochlear duct- middle chamber of the cochlea Spiral organ- also known as the acoustic organ Scala tympani- this is the inferior chamber of the cochlea Spiral ganglion- a mass of neuron bodies on the cochlear nerve tract Scala vestibuli- this is the superior chamber of the cochlea Vestibular membrane- this separates the scala media from the scala vestibuli Vestibular nerve- carries information about equilibrium Otoliths- calcium carbonate protein granules Hair cell- these cells are innervated by the vestibular nerve Supporting cell- these are structural cells between hair cells Otolithic membrane- gelatinous membrane on the stereocilia Macula sacculi- lies on the wall of the sacculae Macula utriculi- lies on the floor of the utricle Which of the structures shown here contain receptor hair cells (macula or crista ampullaris) of equilibrium? A B C Which structure in this figure contains the sense organ for hearing? E A = saccule The SCALA TYMPANI is the most inferior chamber of the spiral organ. The acoustic organ, aka the SPIRAL ORGAN, transduces airborne vibrations into neural signals 2 chambers of the vestibule = saccule + utricle Which is an opening between the middle ear and the vestibule of the inner ear? OVAL WINDOW Which cranial bone contains the bony labyrinth? TEMPORAL BONE The vestibule contains receptors for which sensory modality? EQUILIBRIUM (balance) Accessory structures of the eye: Superior rectus muscle- moves the eyeball up and down Tarsal plate- inferior portion of the eyelid Tarsal glands- glands of the eyelid Cornea- the anterior outer covering of the eye Conjunctiva- mucous membrane covers the inner surface of the eyelid and anterior surface of the eyeball Lateral rectus muscle- moves the eyeball left and right Inferior rectus muscle- moves the eyeball down Trochlea- fibrocartilage ring Superior oblique- this muscle travels along the medial wall of the orbit Superior rectus muscle- this muscle helps move the eye up and down Medial rectus- this muscle is located on top of the superior portion of the eyeball Lateral rectus muscle- moves the eye to the right and left Inferior oblique- this muscle moves the eyeball in a circle Inferior rectus muscle- located on the inferior portion of the eyeballs