Special sense Flashcards Preview

Nursing > Special sense > Flashcards

Flashcards in Special sense Deck (29):
1

location of general sense organs

- exteroceptors (cutaneous)
- visceroceptors
- proprioceptors (joints, muscles, tendons)

2

where are osmoreceptors

hypothalamus → detect changes in osmolarity

3

olfactory R

detect odorant chemical in solutions
- cilia in roof of nasal cavity (olfactory epithelium)
- olfactory bulb/N needs to be covered in mucous to be working
- olfactory centres in temporal lobe → interpretation, integration, memory (limbic system)
- also links to taste

4

7 qualities pf smell

associated with memory
- pepperminty
- musky
- floral
- ethereal (triggers memory)
- pungent
- putrid
- camphoraceous (moth balls)

5

taste (gustation)

- salty (rostral lateral) → Na enter cells
- sour (caudal lateral) → senses HCl, H+ enter cells
- bitter (back) → sense quinine
- sweet (tip) → sense sucrose
- umami → 'meaty/savoury taste' senses MSG

6

papillae

-each pap has 1-100 taste buds
- each bud has 50-150 taste cells (are not neurons)
- form synapses gustatory afferent axons → tastants dissolved in saliva binds to R

7

taste

ANT 2/3 → facial N
POS 1/3 → glossopharyngeal N
- N → medulla → thalamus → taste center in parietal lobe (limbic system to develop memories)

8

structures of ear

- pinna, tragus (ear lobe)
- ex acoustic meatus → leads to tympanic membrane
- mid ear bone → malleolus, incus, stapes
- eustachian tube → mid ear to nasopharynx (equalises pressure b/w ex and mid ear
- oval window
- inner ear

9

cochlear

contains organ of corti
- consist of supporting cells and hair cells

10

how does sound waves vibrate hair cells

sound waves → move endolymph → deform hair cells → open/close channels → AP → cochlear branch of vestibulocochlear N

11

maintaining static equilibrium

by vestibule
- detects head position in relation to gravity/acceleration when motionless

12

dynamic equilibrium

semicircular canal
- detection of movement of endolymph in canal

13

how is hearing impairment established

- poor air conduction (form build up of air cerumen)
- presbycusis → hearing loss associated with ageing (hair cell damage/atrophy)

14

meniere's disease

excessive endolymph accumulation → increase pressure that disrupts balance and hearing

15

fibrous layer of vision

- sclera (white covering eye)
- cornea (outside layer continuous with sclera)

16

vascular layer

- choroid (BS to eye)
- ciliary body (continuous with choroid, and prod aq/virtreous humour)
- iris (circular muscles controlling size of pupil)

17

inner layer

retina
- contains optic disc (blind spot → optic N leaves retina)
- fovea → high conc of cones

optic N (no sensory cells are at entry of optic N)

retinal BV

18

3 types of optic neurons

photoR (rods/cones) → bipolar neurons → ganglion neurons → optic N → occipital lobe

19

ratio of rods and cones

high rods (B&W) : low cones (colour)

20

what prevents eyeball from collapsing

vitreous humour
- fills POS cavity

Aq humour
- fills ANT cavity
- prod. by ciliary body
- drained by canal of schlemm

21

glaucoma

inability to drain aq humour
- damages lens structures

22

physiology of vision

- processes to focus light (IF

23

if >6m away

accommodation, constriction, convergence not required

24

presbyopia

ageing → lose elasticity → inability to bulge and accommodate for near vision

25

myopia

short-sighted
- image focused in front of fovea

26

hyperopia

long-sighted
- image focused behind fovea

27

astigmatism

irregular curvature of cornea (different points of focus on retina)

28

cataracts

cloudy area within lens due to age-related degeneration

29

retinal detachment (retinoschisis)

fluid accumulation → seperates retina from underlying tissues (AMD)