Senses Flashcards
Which photoreceptors are responsible for colour vision?
Where are the majority of these photoreceptors located?
Cone cells
Fovea
What part of the retina is a blind spot?
Optic disc
Where optic axons leave eye
Which cells from the DIRECT pathway from photoreceptors to ganglion cells?
Which cells form the INDIRECT pathway?
DIRECT: Bipolar cells
INDIRECT: horizontal/amacrine cells
Describe the state of photoreceptors in the dark.
What happens in light?
- Depolarized. Releasing NT
* cGMP decreases, Na channels close. NT no longer released.
What is the retinofugal projection ?
Retinofugal projection
Retina –> lateral geniculate nucleus
–> primary visual cortex
What is the primary visual cortex arranged into?
Cortical module (Orientation columns, ocular dominance columns, blobs)
What the the 3 ossicles?
Mallius, incus, stapes
Which ossicle hits oval window of cochlea?
Stapes
Where are the organ of corti and inner hair cells located?
Scarla media (cochlea)
What structure distorts cilia of inner hair cells?
Tectoral membrane
Where is the auditory complex located?
Superior temporal gyrus
Which ion causes depolarization in the mechanoelectrical transduction of sound?
K+ (moves IN to cilia)
K+ channels opened by flexion of cilia
What cranial nerve conveys auditory info to brain?
8
Where are olfactory signals sent after the olfactory bulb?
Pyriform cortex
What cranial nerve is the olfactory nerve?
Cranial nerve 1
Olfactory nerve = axons of olfactory cells that project into olfactory bulb
What kind of receptors do odorants bind to on cilia?
GPCRs
What 2nd messenger is activated in olfactory transduction?
cAMP
opens Na and Ca channels
Where does the pyriform cortex project onto?
Orbitofrontal cortex
Which are the largest taste-sensitive structures?
Circumvalate papillae
Which are the smallest papillae?
Fungiform
What papillae are elongated and located at posterior lateral edge of tongue?
Foliate
What is the gustatory pathway?
Medulla –> thalamus –> gustatory cortex
What are the 2 substructures of the gustatory cortex?
Insula + operculum
