How does The Dogs Nose know?

How Does The Dog’s Nose Know?
This article is the first in a series to introduce the readers to the specifics of canine olfaction. A number of parts will be presented to cover various topics including: canine vs human olfactory systems, does breed or sex affect sense of smell, the accessory olfactory system, factors that affect the sense of smell and an introduction to the genetics of olfaction. If there are any other areas readers wish to be covered, please get in touch.
So to start off the series, What Is Olfaction?
Olfaction is also known as the sense of smell. The olfactory system comprises of the nose, which contains specially adapted cells designed for the detection of odours. These are then linked to a specific part of the brain, known as the olfactory bulb, via nerves. When odour molecules enter the nose, the cells send signals via the nerves to the brain where this information is interpreted.IMG_0483

Image from http://www.biologyjunction.com/olfaction.htm
There are two theories for the mechanism of olfaction; the “lock and key” theory and the vibration theory. These two theories will now be briefly described.
Lock and Key Theory
This is also known as “shape theory” was first proposed in 1949 and is based on the notion that for a smell to be detected, an odour molecule must fit into a receptor on a cell. Only a molecule of a specific size, shape and configuration will fit into a particular receptor to induce a signal to the brain. A modernised version of this theory based on findings from scientific research is known as the odotope or “weak shape” theory. However, similar shaped molecules can often give rise to very different smells which confuses this theory somewhat.
Vibration Theory
This was first proposed in 1928 but was abandoned in favour of the “lock and key” theory. However, a 1996 research paper resurrected the idea. This posits that a molecule must first fit into a receptor on a cell but will only trigger a signal if the molecule has the correct vibrational frequency. However, research testing this theory has so far proven inconclusive.IMG_0484

Image from http://www.sciencefocus.com/feature/health/how-we-smell-competing-theories
Neither of these theories completely explains the phenomenon of olfaction. And so the exact mechanism remains a mystery. The next part in the series will explore the differences between the canine and human olfactory systems in an attempt to explain why the dog’s sense of smell is superior to our own.

For more information on the theories of olfaction, please visit the following websites:
http://www.physics.org/featuredetail.asp?id=83
http://www.bbc.co.uk/bang/article_smell.shtml
http://theconversation.com/whats-that-smell-a-controversial-theory-of-olfaction-deemed-implausible-42449
http://rsta.royalsocietypublishing.org/content/368/1924/3491

References:
Turin L (1996). A spectroscopic mechanism for primary olfactory reception. Chemical senses. 21 (6): 773–91
Moncrieff, Robert Wighton (1949), What is odor? A new Theory. American Perfumer, 54: 453
Buck, L. and Axel, R. (1991) A novel multigene family may encode odorant receptors: a molecular basis for odor recognition. Cell, 65, 175-187.

 

k9WH are grateful to their ‘resident’ scientist for this article.

You May Also Like

1,056 thoughts on “How does The Dogs Nose know?

  1. Pingback: Buy viagra in us
  2. Pingback: cialis from india
  3. Pingback: cialis 5 mg
  4. Pingback: cialis 20mg price
  5. Pingback: cialis price
  6. Pingback: Order viagra
  7. Pingback: is cialis generic
  8. Pingback: buy levitra
  9. Pingback: viagra 100mg
  10. Pingback: viagra 100mg
  11. Pingback: viagra pills
  12. Pingback: ed pills otc
  13. Pingback: best ed medication
  14. Pingback: tadalafil generic
  15. Pingback: viagra for men
  16. Pingback: Viagra or cialis
  17. Pingback: Viagra or cialis
  18. Pingback: vardenafil 10 mg
  19. Pingback: levitra 10mg
  20. Pingback: levitra dosage
  21. Pingback: viagra cheap
  22. Pingback: cash advance
  23. Pingback: personal loan
  24. Pingback: viagra for sale
  25. Pingback: cialis buy
  26. Pingback: cialis 5 mg
  27. Pingback: buy cialis
  28. Pingback: cialis generic
  29. Pingback: 20 cialis
  30. Pingback: viagra 25mg
  31. Pingback: real online casino
  32. Pingback: casino real money
  33. Pingback: casino online
  34. Pingback: buy generic viagra
  35. Pingback: order viagra
  36. Pingback: viagra connect
  37. Pingback: online viagra
  38. Pingback: viagra pills
  39. Pingback: generic viagra
  40. Pingback: order viagra
  41. Pingback: cheap viagra
  42. Pingback: cheap viagra
  43. Pingback: buy viagra online
  44. Pingback: Viagra 130 mg usa
  45. Pingback: tadalafil buy
  46. Pingback: viagra generic
  47. Pingback: cialis price
  48. Pingback: buy Viagra 100 mg
  49. Pingback: buy viagra
  50. Pingback: rx trust pharm
  51. Pingback: Cialis 20mg usa
  52. Pingback: Cialis 60mg online
  53. Pingback: Cialis 20 mg usa
  54. Pingback: sildenafil
  55. Pingback: cheap viagra
  56. Pingback: amaryl 2mg otc
  57. Pingback: viagra buy
  58. Pingback: levitra cialis
  59. Pingback: buy cialis
  60. Pingback: avapro 300mg cheap
  61. Pingback: buy viagra nyc
  62. Pingback: baclofen 10mg uk
  63. Pingback: rxtrustpharm.com
  64. Pingback: cialis stories
  65. Pingback: generic sildenafil
  66. Pingback: sildenafil
  67. Pingback: cheap cialis
  68. Pingback: catapres otc
  69. Pingback: celexa pharmacy
  70. Pingback: RxTrustPharm
  71. Pingback: claritin australia
  72. Pingback: casino online usa
  73. Pingback: casinos online
  74. Pingback: free slots online
  75. Pingback: casino real money
  76. Pingback: gambling casino
  77. Pingback: casino slots
  78. Pingback: best casino games
  79. Pingback: casinos
  80. Pingback: rivers casino
  81. Pingback: cialis miami
  82. Pingback: ed solutions
  83. Pingback: quick loans
  84. Pingback: blue pill for pain
  85. Pingback: viagra cheapest
  86. Pingback: cialis 20mg pills
  87. Pingback: order real viagra
  88. Pingback: Buy viagra now
  89. Pingback: type writer paper
  90. Pingback: buy papers online
  91. Pingback: help my essay
  92. Pingback: help my essay
  93. Pingback: cleocin pharmacy
  94. Pingback: sildenafil buy nz
  95. Pingback: Viagra overnight
  96. Pingback: colchicine tablet
  97. Pingback: cialis everyday
  98. Pingback: cheapest coreg
  99. Pingback: cialis online
  100. Pingback: essayhelpbgs.com
  101. Pingback: sildenafil drug
  102. Pingback: cost of crestor
  103. Pingback: buy cheap viagra
  104. Pingback: dapsone caps nz
  105. Pingback: ddavp tablet
  106. Pingback: Viagra 50 mg
  107. Pingback: diamox price
  108. Pingback: differin pills
  109. Pingback: doxycycline price
  110. Pingback: flomax pharmacy
  111. Pingback: geodon 20mg cost
  112. Pingback: cheap cialis
  113. Pingback: imitrex price
  114. Pingback: cialis order
  115. Pingback: canadian viagra
  116. Pingback: check my reference
  117. Pingback: generic for viagra
  118. Pingback: cost of imuran
  119. Pingback: lamisil cheap
  120. Pingback: generic sildenafil
  121. Pingback: buy macrobid
  122. Pingback: order meclizine
  123. Pingback: viagra san diego
  124. Pingback: sildenafil citrate
  125. Pingback: micardis otc
  126. Pingback: cheap Zovirax
  127. Pingback: mobic uk
  128. Pingback: dapoxetine
  129. Pingback: periactin pharmacy
  130. Pingback: prevacid 15mg usa
  131. Pingback: cheap viagra
  132. Pingback: pulmicort generic
  133. Pingback: viagra like drugs
  134. Pingback: pyridium nz
  135. Pingback: remeron tablet
  136. Pingback: buy allegra 120mg
  137. Pingback: seroquel generic
  138. Pingback: order skelaxin
  139. Pingback: viagra prices
  140. Pingback: thorazine pharmacy
  141. Pingback: valtrex purchase
  142. Pingback: buy vantin
  143. Pingback: zanaflex 4mg cheap
  144. Pingback: imp source
  145. Pingback: zocor 40mg usa
  146. Pingback: buy zovirax 400 mg
  147. Pingback: meaning of viagra
  148. Pingback: meclizine generic
  149. Pingback: atomoxetine usa
  150. Pingback: sildenafil generic
  151. Pingback: dutasteride tablet
  152. Pingback: cialis coupon
  153. Pingback: cialis online
  154. Pingback: rosuvastatin nz
  155. Pingback: sildenafil price
  156. Pingback: viagra
  157. Pingback: venlafaxine price
  158. Pingback: amitriptyline otc
  159. Pingback: tadalafil
  160. Pingback: qlroxuho
  161. Pingback: male ed drugs
  162. Pingback: order tamsulosinmg
  163. Pingback: pills for ed
  164. Pingback: qqbkrspv
  165. Pingback: what do viagra do
  166. Pingback: lasix generic
  167. Pingback: cleocin price
  168. Pingback: isosorbide canada
  169. Pingback: augmentin tablets
  170. Pingback: bactrim online
  171. Pingback: trimox capsules
  172. Pingback: pastillas cialis
  173. Pingback: cialis
  174. Pingback: cialis sale 20mg
  175. Pingback: indomethacin otc
  176. Pingback: compra de viagra
  177. Pingback: Google
  178. Pingback: furosemide 12.5
  179. Pingback: viagra online usa
  180. Pingback: start clomid
  181. Pingback: clomid 200mg
  182. Pingback: essayhelpof.com
  183. Pingback: order ed pills
  184. Pingback: write my thesis
  185. Pingback: neurontin 330 mg
  186. Pingback: click here
  187. Pingback: propecia gyno
  188. Pingback: propecia cost
  189. Pingback: Herbal incense
  190. Pingback: cat essay writer
  191. Pingback: Electronics
  192. Pingback: buy guns online nj
  193. Pingback: cialispills online
  194. Pingback: canada pharmacy
  195. Pingback: cialis 200 mg.
  196. Pingback: neurontin abuse
  197. Pingback: paxil 25 mg
  198. Pingback: buy card
  199. Pingback: delta 8 near me
  200. Pingback: online consultants
  201. Pingback: best price cialis
  202. Pingback: buy guns online
  203. Pingback: 샌즈카지노
  204. Pingback: 메리트카지노
  205. Pingback: clomiphene tablets
  206. Pingback: 코인카지노
  207. Pingback: 우리카지노
  208. Pingback: 퍼스트카지노
  209. Pingback: Vidalista 40mg
  210. Pingback: buy metformin uk
  211. Pingback: Guns for sale
  212. Pingback: SEO Services Benin
  213. Pingback: finasteride cost
  214. Pingback: best ed drugs
  215. Pingback: online drugs
  216. Pingback: Hypodermic Needle
  217. Pingback: honda dirt bikes
  218. Pingback: dexedrine for sale
  219. Pingback: Nanimo SEO
  220. Pingback: Cephalexin
  221. Pingback: research cialis
  222. Pingback: buy cialis 36 hour
  223. Pingback: QUEBEC BLUE STRAIN
  224. Pingback: rwqz
  225. Pingback: Website
  226. Pingback: strap on vibrator
  227. Pingback: CARGO VESSEL
  228. Pingback: service in canada
  229. Pingback: tinderentrar.Com
  230. Pingback: in canada
  231. Pingback: female vibrators
  232. Pingback: lovoo wikipedia
  233. Pingback: realistic dildo
  234. Pingback: ed meds online
  235. Pingback: hk vp9 sk
  236. Pingback: about canada
  237. Pingback: slot online
  238. Pingback: sex toys
  239. Pingback: anal sex toy
  240. Pingback: canada rx pharmacy
  241. Pingback: Gun Shops near me
  242. Pingback: top rated ed pills
  243. Pingback: pocket pussy
  244. Pingback: mexican viagra
  245. Pingback: Pinball machines
  246. Pingback: PARROTS FOR SALE
  247. Pingback: software review
  248. Pingback: FLOUR MILL
  249. Pingback: kratom for sale
  250. Pingback: doxycycline 100mg
  251. Pingback: double dong
  252. Pingback: viagra online usa
  253. Pingback: how much is viagra
  254. Pingback: cytotmeds.com
  255. Pingback: ed supplements
  256. Pingback: Delta 8
  257. Pingback: buy delta 8 THC
  258. Pingback: weed near me
  259. Pingback: plaquenil for ra
  260. Pingback: buy weed online
  261. Pingback: Seattle Weekly
  262. Pingback: buy weed online
  263. Pingback: ptr 9ct for sale
  264. Pingback: ivermectin 3 mg
  265. Pingback: Komunitas obligasi
  266. Pingback: cost of ivermectin
  267. Pingback: MUT
  268. Pingback: drugs online
  269. Pingback: Roofing Services
  270. Pingback: Chaise Lounge Sofa
  271. Pingback: Hedgehog For Sale
  272. Pingback: viagra from india
  273. Pingback: male sex toys
  274. Pingback: learn more
  275. Pingback: order juul pods
  276. Pingback: order kush online
  277. Pingback: Buy Ruger Online
  278. Pingback: cialis canada sale
  279. Pingback: women's viagra
  280. Pingback: viagra best prices
  281. Pingback: US Trending News
  282. Pingback: regcialist.com
  283. Pingback: best pocket pussy
  284. Pingback: sexual health
  285. Pingback: stromectol tablets
  286. Pingback: anal play
  287. Pingback: website
  288. Pingback: ivermect use
  289. Pingback: buy weed uk
  290. Pingback: panty vibe
  291. Pingback: vibrator for women
  292. Pingback: pocket pussy
  293. Pingback: their website
  294. Pingback: MILF Porn
  295. Pingback: male masturbator
  296. Pingback: circumcised dildo
  297. Pingback: Thc jull pods
  298. Pingback: kaynarca escort
  299. Pingback: streamcomplet
  300. Pingback: streaming gratuit
  301. Pingback: film streaming
  302. Pingback: CTRLCOIN
  303. Pingback: drug amlodipine
  304. Pingback: Content Source
  305. Pingback: orgasm
  306. Pingback: adam and eve
  307. Pingback: 1xbit review
  308. Pingback: best in ottawa
  309. Pingback: 메이저사이트
  310. Pingback: pmang-no1.com
  311. Pingback: natural viagra
  312. Pingback: ivermectin drug
  313. Pingback: ed drug comparison
  314. Pingback: Diablo strain
  315. Pingback: indola
  316. Pingback: cheap ed drugs
  317. Pingback: rx cialis
  318. Pingback: tab cialis 20mg
  319. Pingback: OXYCODONE FOR SALE
  320. Pingback: male sex toy
  321. Pingback: anal vibrator
  322. Pingback: viagra alternative
  323. Pingback: cialis best price
  324. Pingback: mp3juices
  325. Pingback: viagra for sale
  326. Pingback: STIIIZY Carts
  327. Pingback: cialis sample
  328. Pingback: viagra samples
  329. Pingback: clomid 100mg
  330. Pingback: canada viagra
  331. Pingback: Mac akku ersetzen
  332. Pingback: apo prednisone
  333. Pingback: best male sex toys
  334. Pingback: Serengeti tours
  335. Pingback: doxycycline 100 mg
  336. Pingback: generic for viagra
  337. Pingback: ivermectin 3 mg
  338. Pingback: ivermectin scabies
  339. Pingback: ivermectin cvs
  340. Pingback: p320 m17
  341. Pingback: buy pentobarbital
  342. Pingback: magic mushrooms
  343. Pingback: cheap medication
  344. Pingback: cheap medications
  345. Pingback: magic mushrooms
  346. Pingback: le tadalafil
  347. Pingback: cialis mg
  348. Pingback: sildenafil 20mg
  349. Pingback: juul cartridges
  350. Pingback: Cali weed for sale
  351. Pingback: 3080 ftw3 msrp
  352. Pingback: buy hex dumbbells
  353. Pingback: tamoxifen men
  354. Pingback: RissMiner
  355. Pingback: ivermectin 4
  356. Pingback: dizziness
  357. Pingback: bitcoin
  358. Pingback: kihejo
  359. Pingback: ivermectin 500ml
  360. Pingback: zithromax otc
  361. Pingback: viagra sale
  362. Pingback: savage grow plus
  363. Pingback: male masturbators
  364. Pingback: ddm4v7 pro
  365. Pingback: cialis vs viagra
  366. Pingback: Seiko Alpinist
  367. Pingback: pharmacy Canada
  368. Pingback: herb viagra
  369. Pingback: walgreens viagra
  370. Pingback: viagra bestellen
  371. Pingback: happyLuke
  372. Pingback: ivermectin cost
  373. Pingback: viagra receptfritt
  374. Pingback: buy amoxil canada
  375. Pingback: 214 gabapentin
  376. Pingback: online viagra
  377. Pingback: plaquenil 300
  378. Pingback: quineprox 50
  379. Pingback: 200 mg prednisone
  380. Pingback: prednisone 25
  381. Pingback: viagra pill
  382. Pingback: priligy buy online
  383. Pingback: provigil drug buy
  384. Pingback: modafinil coupons
  385. Pingback: stromectol cream
  386. Pingback: ventolin 95mcg
  387. Pingback: zithromax pills
  388. Pingback: chewable viagra
  389. Pingback: buy viagra
  390. Pingback: cost of viagra
  391. Pingback: getzq.com
  392. Pingback: viagra generico
  393. Pingback: valtrex 500mg uk
  394. Pingback: The NMD News
  395. Pingback: happyruck.com
  396. Pingback: goodrx sildenafil
  397. Pingback: dankwood
  398. Pingback: sildenafil pills
  399. Pingback: generic pills
  400. Pingback: macross delta
  401. Pingback: party sex games
  402. Pingback: pleasure kits

Comments are closed.