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Question 1

biological function of olfaction

Answer 1

survival: find and select food, avoid predator
communication: recognize members of family, mother/infant bond, identify territory, mating

Question 2

why do we sniff

Answer 2

only 5% of nose has epitheliam so sniffing maximizes coverage of air interact to portion of the nose

Question 3

olfactory epithelium

Answer 3

5-10cm in the roof of the nasal cavity lined

seperates nose from brain

Question 4

structure of olfactory epithelum

Answer 4

mucus liknes the MOE
- mucus produced by bowmans glands under basal lamina
olfactory receptor neurons:
- unmyelinated and slow conducting (dont have far to go)

Question 5

regeneration of neurons in MOE

Answer 5

made on a monthly basis

Question 6

what does odor perception depend on

Answer 6

the concentration of odorant

Question 7

enantiomers

Answer 7

produce different percpetions

D carvone- spearment/ L-carvone- caraway

Question 8

olfactory receptor potentials

Answer 8

generated in the cilia of receptor neurons not SOMA

receptor potentials- inward current

Question 9

cilia of ORNs

Answer 9

mucus- odorant binding proteins that facilitate detection of odors

Question 10

odorant receptor super family

Answer 10

gene family- can detect many odors because thousands of egnes encode for receptors
- receptors have 7 TM domains (G protein coupled)

Question 11

buck and axel hypothesis

Answer 11

odorant receptors are GPCR
receptors family could be large and diverse or restricted
expression of receptors is restricted to Main olfactory epithelium (MOE)
designed primers to anneal to conserved regions spanning 700bp region of putative receptor

Question 12

reverse transcription

Answer 12

enzyme synthesize a complimentary 2nd strand of DNA

• chews up RNA
• prepares from olfactory epithelium RNA and subjected to PCR amplification

Question 13

polymerase chain reaction

Answer 13

way to increase the amount of DNA being tested
can make.1 into millions to study
- degenerate primers complimentary to DNA
- extend SS into DS
- clue that made realize there are many receptors

Question 14

g protein coupled receptors in ordorant transduction

Answer 14

odorant binds to –> G olf targets Adenyl cyclase 3
AC3 produces cAMP which activates Na/Ca channel
- discovered by knocknig out and measuring current

Question 15

Gy13

Answer 15

critical subunit to heterotrimeric g protein

• found no response in KO
• took much longer time to locate buried pellet

Question 16

how is depolarization mediated

Answer 16

1. CNG channel
2. Cl efflux
3. Na/Ca exchanger
   less clear what happens in amplificaiton steps

Question 17

Ca activated Cl currents

Answer 17

present bc current is lost

Question 18

perforated patch

Answer 18

induce little channel (perforation) that allows + ions to flow but not -
- maintain existing intracellular Cl and doesnt disrupt Cl homeostasis

Question 19

maintain of Cl intracellular

Answer 19

NKCC1 - in

KCC2 - out

Question 20

Ca activated Cl currents

Answer 20

put in Cl blocker- current decaying current

- blocks

Question 21

ANO2

Answer 21

cilial calcium activated chloride channel that mediates olfactory amplification