Histology, Physiology, Pathology Flashcards
epithelium of platine tonsils is…
squamous epi
epi of pharyngeal tonsils (adenoids) is…
ciliated pseudo stratified columnar epi > sq epi
way to remember epitheliums
where food goes= squamous epithelium
where air goes= columnar epithelium
how does taste occur
sensory receptors in taste buds > synapse with afferent nerve cells > signals conveyed via cranial nerves to gustatory areas in brain
what are the 3 papillae in tongue (sites of taste buds)
filiform, valate, foliate
CN VII carries taste signals from…
CN IX carries taste signals from…
CN X carries taste signals from…
CN VII= ant 2/3rds of tongue (chrodae tympani)
CN IX= post 1/3rd
CN X= all other areas
3 types of taste pathology
ageusia, hypogeusia, dysguesia
how does smell occur
smell enters nasal cavity > passes olfactory cleft where becomes aqueous > mucus carries to olfactory neuroepithelium > olfactory cilia pick up odourant and pass it through receptor cell where become olfactory nerve fibres > pierce the cribriform plate > enter olfactory bulbs > synapse 2nd order neurones > signal passes through olfactory tract and enters temporal lobe
what 4 things does the olfactory epithelium contain
bi-polar neurones, basal cells, support cells, duct cells (from bowman’s glands- secretes mucus)
what are the 4 neural olfactory systems
CN 1 (olfactory nerve), CN 0 (nervus terminalis), accessory olfactory system, CN V (more protective)
what does the odourant have to be to be smelled
volatile and water soluble
pathology of smell
ansomia, hyposmia, dysosmia, phantosmia
how does hearing occur
sound collected and funnelled in outer ear > hits tympanic membrane > pressure waves move the ossicles in inner ear where more energy is generated > hits oval window and stapes > cochlear apparatus receives high energy pressure waves and the perilymph/endolymph is vibrated > hair cells at organ of corti stimulated generating AP > AP travels along cochlear nerve (CN VIII branch)
frequency dictates _____, and amplitude dictates _____
pitch, intensity
what are the 3 components of the cochlea
scala tympani, scala media, scala vestibuli
why does the middle ear need to generate more energy
because it requires more energy to vibrate fluid in comparison to air molecules
difference between inner and outer hair cells is…
inner: perceive sound and relay to brain
outer: modulate sound
the Eustachian tube is physiologically closed, what muscle opens it to equalise pressure between nasopharynx and ear?
tensor palatini muscle (CN V3 innervation)
what is responsible for balance
hair cells are responsible (kinocilium and the stereoculium- hair cells of vestibular apparatus). these move with direction of movement.
T/F: the SC canals in vestibular apparatus provide the feeling of gravity
F: the utricle and the saccule (otolith organs) lend the feeling of gravity, SC canals detect movement
what is the vestibulo-ocular reflex
when head moves, eyesight can remain fixed.
this is achieved by inhibiting certain intra-ocular muscles .
what does Poiseuille’s equation and Venturi effect state?
as airway diameter reduces, the air resistance inc 4 fold
what are salivary glands made up of (3 components)
acinar (secretes digestive enzymes), ductular (myoepithelial cells), mutinous component (glycoproteins)
what are some ear pathologies
otitis media, cholestatoma, tumours (Sq cell carcinoma, basal cell carcinoma, other rare cancers e.g. vestibular schwanoma)
