Week 3- Senses And Sensory Receptors

Question 1

List the special senses

Answer 1

Taste
Smell
Vision
Hearing and balance

Question 2

Name the 2 types of senses

Answer 2

Special
General

Question 3

What are general sense as associated with

Answer 3

Touch

Question 4

Name the 5 D’s and 3 N’s

Answer 4

Diplopia- double vision
Dysarthia- difficulty speaking
Dysphagia- hard to swallow
Drop attack- falls
Dyskinesea- involuntary movement

Nyastagmus- involuntary eye movement
Nausea- sickness
Numbness - of face nerves

Question 5

How do special senses work

Answer 5

Gather sensory info and change it into nerve impulses

Question 6

Describe first order neurons

Answer 6

First Order Neurons: Detect a stimulus and transmits a signal to thespinal cord

Question 7

Describe second order neurons

Answer 7

• Second Order Neurons: Continues as far as the gateway-thethalamus- at the upper end of the brainstem•

Question 8

Describe third order neurons

Answer 8

• Third Order Neurons: Carries the signal the rest of the way to thesensory region of the cerebral cortex

Question 9

Label the pathway of olfactory system

Answer 9

• Olfactory receptor cells of the epithelium and olfactory nerves >

mitral cell and tufted cell (2 order)

Olfactory bulb>
olfactory tract and olfactory striae

> Olfactory cortical areas
primary olfactory cortex and secondary olfactory cortex (inferior)

Question 10

List the 8 primar odors

Answer 10

Camphorous
Fishy
Malty
Minty
Musky
Spermatic
Sweaty
Urinous

Question 11

What cells detect (1st order) for olfactory epithelium

Answer 11

Olfactory receptor cells
Supporting cells
Basal/progenitor cells

Question 12

What is the olfactory bulb

Answer 12

Flattened oval mass of grey matter, lying just above the cribiform plate

Question 13

Describe secondary olfactory cortex

Answer 13

Helps to explain strong associations between odors and memory, emotion and endocrine function

Question 14

What is fungiform papillae

Answer 14

most common

Raised lingual structures which contain 3-5 taste buds in each

Question 15

What is circumvallate papillae

Answer 15

Found at base of tongue
7-10 pp

Sensitive to bitter taste
Involved in gag reflex
Associated salivary glands release saliva and help regulate circumvallate papillae

Question 16

Describe foliate papillae

Answer 16

Verticals folds on postolateral sides
Perceive taste

rear end of tongue. posteriolateral

Question 17

What is amyglada

Answer 17

Part of the brain associated with fear, emotions and motivations
Medial temporal lobe

Question 18

What nerves are associated with salivation, starting digestive process

Answer 18

• CN 7 – Facial Nerve – Taste – Anterior 2/3 of the tongue.•
Main taste centre – Geniculate Ganglion.•

CN 9 – Glossopharyngeal Nerve – Taste – Posterior 1/3 tongue.•
Main taste centre – Nucleus tractus Solitarius•

CN 10 - Vagus nerve

Question 19

What is the only site neurons are exposed

Answer 19

Olfactory receptor cells( neurons)

Question 20

What is the only site neurons can regenerate

Answer 20

Olfactory epithelium (renewal of olfactory receptors)

Question 21

Which recepoirst are modified neurons

Answer 21

Olfactory receptors and photoreceptors (rods and cones)

Question 22

What is the only sensory pathway where second order neurons reach cortex without relay in thalamus

Answer 22

Olfactory pathways

Question 23

List general senses

Answer 23

Pain
Temp
Touch
Pressure
Vibratin

Question 24

What is olfaction a part of

Answer 24

Limbic system (HOME)

Question 25

What cranial nerves are associated with taste

Answer 25

Facial 7 Glossopharyngeal 4 Vagus 5

Question 26

Function of vestibular nerve

Answer 26

Responsible for afferent and efferent fibres that control BALANCE and EQUILIBRIUM

Question 27

Function of cochlear nerve

Answer 27

‘Auditory nerve’ Carries efferent and afferent Fibres for HEARING

Question 28

list vestibular pathway neurons

Answer 28

1- vestibular ganglion* 2= vestibular nuclei in medulla oblongata* 3 - Thalamus* From there fibres project to the vestibular area of the cortex

Question 29

What is the spiral ganglion

Answer 29

Group of neuron cell bodies in central axis of cochlea superior to the cochlear (centre of spiral)

Question 30

function of iris

Answer 30

controls hwo much light enters by changing shape

Question 31

describe neurons in sight

Answer 31

1= bipolar cells of the retina and receives visual information from the neuroepithelial cell of the retina(e.g. rods and cones) 2= ganglion cell of retina- axon lie in optic nerve and carry to optic chiasm and proximal optic tracts 3= cell body in lateral geniculate nucleus in thalamus axon project to visual cortex in a band of fibers call optic radiation

Question 32

describe vision

Answer 32

light enters lens. images are inverted and reversed onto retina (back of eye) rods detect low light and cones detect color. optic disc where axons gather to form optic nerve and leave the eye retinal ganglion cells send their axons to optic nerve. exit via optic canal and sphenoid bone. partial crossing at optic chiasm optic tracts form synapses on neurons in lateral geniculate nucleus of the THALAMUS. projects to primary visual cortex. other fibers enter superior colliculus forming extrageniculate visual pathways which project to pretectal area which is important for pupillary light reflex and control to direct visual attention and eye movement. fibers move back to primary visual cortex

Question 33

role of rod cells

Answer 33

Rods – more rods than cones and they do not detect colours but detect well in lowlight

Question 34

role of cone cells

Answer 34

Cones – detect colour and have higher spatial and temporal resolution.*

Question 35

name the 2 type of visual pathways

Answer 35

dorsal ventral

Question 36

describe dorsal pathway

Answer 36

carries visual stimulus signals from visual cortex to parietal cortex along the way, it passes through areas which calculate objects location, creating an action plan. plans motion and timing (duck) non conscious

Question 37

describe the ventral pathway

Answer 37

visual processing areas, adding perception such as shape, colour. passed temporal lobe where it is matched/compared to visual memories in order to achieve recognition some continue to frontal lobe where info is assessed for meaning and significance conscious perceptin

Question 38

what is the optic chasm

Answer 38

the corss over junction where the signals from the two optic nerves cross over

Question 39

Name one unique feature of olfactory pathway

Answer 39

Skips thalamus and goes straight to cortex

Question 40

Name cranial nerves involved with taste sensation

Answer 40

Glossopharygngeal, facial vagus

Question 41

Name 2 cranial nerves arising from midbrain that are associated with function of the eye

Answer 41

Occuolomotor nerve Trochlear

Question 42

what is different about the olfactory pathway

Answer 42

-only 2 neurons -no relay to the thalamus. directly to the cortex.

Question 43

what is the olfactory epithelium

Answer 43

area within each nasal cavity that contains the olfactory receptors

Question 44

list taste buds

Answer 44

fungiform papillae circumvallate papillae foliate

Question 45

name order of taste

Answer 45

1= facial, glossopharangeal and vagus nerve 2= medulla oblongata 3= cortical taste area

Question 46

name cells within taste buds

Answer 46

gustory cell supporting cell

Question 47

describe hearing process

Answer 47

sound waves travel through external auditory cannal. vibrate the membrane and middle ear ossicles wave travels through endolymphatic fluid of cochlea fluid vibrates the cortis basilar membrane stimmulating inner and outer heairs hair cells transmit AP to bipolar neurons in spiral ganglian auditory system transmits the stimulus responsible from hearing receptor to auditory area in temporal lobe