Olfactory Flashcards Preview

Block 5 module 3 COPY > Olfactory > Flashcards

Flashcards in Olfactory Deck (67):
1

the olfactory system lies in the __________ of each nostril

superior part

2

olfactory mucosa is innervated by _____

CN I & V

3

CN responsible for irrtitative character of some odorants

CNV trigeminal

4

Receptor cells for smell sensation are _______

olfactory cells

5

glia like supporting cells of the olfactory system

sustentacular cells

6

These are found among the olfactory cells and they secrete mucus onto the _______

Bowman's glands; olfactory membrane surface

7

These cells continue to divide to produce new olfactory receptor cells that have short life spans

basall cells

8

Basal cells produce

olfactory receptor cells

9

the ones that respond to olfactory chemical stimuli

Olfactory Cilia

10

odor qualities that can be sensed

floral
ethereal
musky
camphor
putrid
pungent
pepperminty

11

olfactory cilia have _______ long molecules that thread their way thru the membrane about 7 times

receptor proteins

12

the inside folding of receptor proteins is coupled to a ________ made of ______

G-proteins; 3 subunits

13

What are olfactory bulb and tract

anterior outgrowths of brain tissue from the brain's base

14

anterior
outgrowths of brain tissue from the brain's
base.

olfactory bulb and tract

15

the olfactory bulb lies over the _______

cribriform plate

16

the olfactory bulb separates the ______ from the _______

brain cavity from the upper nasal cavity

17

These allow small nerves to pass from the olfactory membrane to the olfactory bulb

cribriform plate perforations

18

the cribriform plate perforations allow small nerves to pass from________ to ______

olfactory membrane to olfactory bulb

19

where does the olfactory cells' axon terminate

globular glomeruli within the olfactory bulb

20

principal cells of the olfactory bulb

mitral cells

21

olfactory cells are ______ and _____

excitatory and glutaminergic

22

the mitral cells project through the __________ and ________ to the ______ and _______

olfactory tract and lateral olfactory stria to the
primary olfactory cortex and amygdala.

23

Mitral & tufted cell bodies lie in the _______ superior to the ________.

olfactory bulb; glomeruli

24

a junction between two nerve cells, consisting of a minute gap across which impulses pass by diffusion of a neurotransmitter

synapse

25

what are synapses

junction between 2 nerve cells with a minute gap where impulses pass by diffusion of a neurotransmitter

26

the dendrites of mitral and tufted cell bodies receive synapses from

olfactory neurons

27

inhibitory neurons connecting 1 glomerulus to another

periglomerular cells

28

these make reciprocal synapses with mitral and tufted cells

granule cells

29

olfactory bulbs contain _______ and _______

periglomerular cells and granule cells

30

mitral or tufted cells excite granule cells by releasing _____

glutamate

31

what inhibit mitral or tufted cells

granule cells

32

the mitral or tufted cells release glutamate to

excite granule cells

33

odorant substance binds with _________ in the ___________

receptor proteins; olfactory cilium membrane

34

on excitation of receptor protein what happens then

an alpha subunit breaks away from the G-protein

35

alpha subunit activates _______ attached to the inside of the ciliary membrane near the receptor cell body

adenylyl cyclase

36

what does the adenylyl cyclase do

converts ATP to cAMP

37

cAMP activates

gated sodium ion channel

38

Na ions increase ______ in the ______ direction

electrical potential; positive

39

olfactory neuron excitation and AP transmission into CNS via ______-

olfactory nerve

40

_______ are the only substances that can be sniffed into the nostrils can be smelled

volatile substances

41

Stimulating substances must be atleast

slightly water soluble and slightly lipid soluble

42

why stimulating substances must be lipid soluble

lipid constituents of the cilium are a weak barrier to nonlipid soluble odorants

43

rate of olfactory nerve impulses corresponds to

logarithm of stimulus strength

44

olfactory receptors adapt about _______ in the 1st second after stimulation

50%

45

where does most additional adaptation to smell occurs

within the CNS

46

Where does centrifugal nerve fibers pass and its direction along the olfactory tract

olfactory regions of the brain; backward

47

centrifugal nerve fibers terminate on ______ in the ______

special inhibitory granule cells in the olfactory bulb

48

What happens to CNS after onset of olfactory stimulus

it develops strong feedback inhibition to suppress relay of smell signals through the olfactory bulb

49

smell is concerned more with detecting ______ than _____

presence or absence of odors than quantitative detection of intensities

50

Part of the brain that originally subserved
olfaction evolved into the

limbic system

51

ipsilateral olfactory trigone aka

olfactory tubercle

52

integrated signals pass along the olfactory tract and centrally diverge to the ______ or terminate in the _______. axons then project to the _______

anterior commisure; ipsilateral olfactory trigone; primary olfactory cortex, entorhinal cortex and amygdala

53

Brodman's area for primary olfactory cortex

34

54

the brimary olfactory cortex overlies the

uncus

55

olfactory tract enters the brain at the _________, between _____ and ______-

anterior junction between mesencephalon and cerebrum

56

the olfactory tract divides into pathways, one going to _______ and the other to _______

medial olfactory area; lateral olfactory area

57

the septal nuclei feed into the ______ and _____

hypothalamus and other primitive limbic system portions

58

this feed into the hypothalamus &
other primitive limbic system portions

septal nuclei

59

medial olfactory area aka

very old olfactory system

60

lateral olfactory area aka

less old olfactory area

61

lateral olfactory area is composed of

prepyriform cortex and cortical portion of the amygdaloid nuclei

62

the lateral olfactory area does not pass through the

thalamus

63

only area that does not pass first
through the thalamus.

lateral olfactory area

64

inability to smell

anosmia

65

diminished olfactory sensitivity

hposmia or hypesthesia

66

hyperosmia

enhanced olfactory sensivity

67

this may cause olfactory hallucinations

lesions in the parahippocampal uncus