Olfactory organ

Odor Relating to the sense of smell, a substance that stimulates the olfactory organ, allowing us to detect if a smell is pleasant or unpleasant. 

It seems evident therefore that the unsatisfied affinity of an odoriferous body plays a fundamental part in the production of its odour by reason of one or more chemical reactions taking place in the olfactory organ the reactions must necessarily be complicated and rapid. They are at present entirely unknown and problematical, but no very great progress in the knowledge of this subject is likely to be made until the chemical properties of the osmoceptors have been determined. 

Jacobson s Organ must be a precision olfactory organ which can be excited by a minima amount of odourants". 

Fishelson L. and Baranes A. (1997). Ontogenesis and cytomorphology of the nasal olfactory organs in the Oman shark, lago omanensis (Triakidae), in the Gulf of Aqaba. Anat Rec 249, 409-421. 

Hagelin, L.-O. and Johnels, A. (1955). On the structure and function of the accessory olfactory organ in lampreys. Acta Zool 36, 113-125. 

Hansen A., Reiss J.O., Gentry C.L. and Burd G. (1998). Ultrastructure of the olfactory organ in the clawed frog, Xenopus laevis during larval development and metamorphosis. J Comp Neurol 398, 273-288. 

Hansen A. and Zeiske E. (1998). The peripheral olfactory organ of the zebrafish, Danio rerio an ultrastructural study. Chem Senses 23, 39-48. 

Jones F., Pfeiffer C. and Asashima M. (1994). Ultrastructure of the olfactory organ of the newt, Cynops pyrrhogaster. Ann Anat 176, 269-275. 

Muller J. and Marc R. (1984). Three distinct morphological classes of receptors in fish olfactory organs. J Comp Neurol 222, 482-495. 

Oikawa T., Suzuki K., Saito T.R., Tatahashi K.W., et al. (1998). Fine structure of three types of olfactory organs in Xenopus laevis. Anat Rec 252, 301-310. 

Takami S., Luer C. and Graziadei P. (1994). Microscopic structure of the olfactory organ of the Cleamose Skate, Raja eglanteria. Anat Embryol (Berl) 190, 211-230. 

Taniguchi K., Arai T. and Ogawa K. (1993). Fine-structure of the septal olfactory Organ of Masera, and its associated gland in the Golden Hamster. J Vet Med Sci 5, 107-116. 

Thornhill R.A. (1972). Ultrastructure of the accessory olfactory organ in the River Lamprey (Lampetra fluviatilis). Acta Zool 53, 49-56. 

Zeiske E.B., Melinkat R., Breucker H. and Kux J. (1976). Ultrastructural studies on the epithelia of the olfactory organ of cyprinodonts (Teleostei, Cyprinodontoidea). Cell... 

Zeiske E.B., Theisen B. and Breuckner H. (1989). Olfactory organs in pelagic and benthic elasmobranchs. Zool Fortsch 35, 370-372. 

Saucier, D., L. Astic, P. Rioux, and F. Godinot. 1991b. Histopathological changes in the olfactory organ of rainbow trout (Oncorhynchus mykiss) induced by early chronic exposure to a sublethal copper concentration. Canad. Jour. Zool. 69 2239-2245. 

The results demonstrate (i) that in turbulent odor plumes, purely chemical spatial gradients can be calculated when measuring with sensors scaled to lobster olfactory organs, (ii) that rapid odor access to the lobster s olfactory organs (under low ambient flow conditions) is accom-... 

When comparing the dust-borne concentrations of butyric acid and p-cresol with the odour thresholds it seems that the concentrations are too small to be relevant for an odour nuisance. However, if the dust is removed from the gas phase of the air from animal houses the odour disappears (39), (40), (14). This supports the opinion of HAMMOND et al. (40) that the odor is concentrated on the dust particles. The authors conclude from their data that the concentration of the two odorants butyric acid and p-cresol is about 4TO7 greater on an aerosol particle than it is in an equal volume of air. Thus, an aerosol particle deposited on the olfactory organ carries odour equivalent to a much greater volume of air (40). These considerations indicate that dust from animal houses should be taken into account in connection with odour emission/immission measurements not only by chemical analysis but by sensory evaluations using olfactometers without dustfilters, as well. 

Elasmobranchs have their paired olfactory organs on the ventral side near the mouth. As the fish takes the respiratory water current into the mouth, water passes through the olfactory sacs. Thus, elasmobranches use the respiratory water current for supplying the olfactory organ with waterborne stimuli. 

By contrast, bony fish have their olfactory organs on the dorsal side of the snout at some distance from the mouth. The olfactory system in fish involves the first (olfactory) cranial nerve, while the ninth (glossopharyngeal) and other nerves serve the sense of taste. 

FIGURE 5.2 The olfactory organ in fish, (a) The nostril positions in sculpin (Cottidae) b) nostril position in spiny eel (Mastacembelidae) (c) a skin flap separates in- and outflow, an arrangement typical for bony fish (here Catastomidae) (d) the olfactory lamellae are located in the floor of the olfactory capsule (here minnow, Phoxinus). (From C. E. Bond Biology of Fishes.)... 

In the frog Rana temporaria, the VNO shares the nasal compartments with the main olfactory organ. The VNO has three cavities, and water enters from the external nares via two fissures. The VNO is used to sample water while the frog is submerged, while above water air is inhaled and the olfactory system stimulated (D0ving etal., 1993). 

Even marine mammals may use airborne odors for food detection. Baleen whales (Mysticeti) feed on krill near the ocean s surface. Oldtime Antarctic whalers noted a krill odor near large schools of krill. Cruising at the surface and inhaling periodically, baleen whales may detect krill odor. Anatomically, they have a well-developed olfactory organ (Cave, 1988), in contrast to toothed whales (Kusnetzov, 1988). 

Enantiomeric compounds differ from one another only in two aspects The chiroptical characteristics (optical rotation) and the speed of their reaction with chiral molecules. The human olfactory organ is also capable of distinguishing chiral molecules. The odor quality and potency of enantiomeric compounds may show considerable differences. Thus, distinct differentiation in odor perception could be observed in the pairs of enantiomeric oxygenated monoterpenoid odorants. " However, the... 

Aromas (or odors) are the signals perceived by the olfactory organs, tastes are the signals perceived by the lingual organs, and flavors are the simultaneous perceptions of the other two. 

Burgess, M. F. and Derby, C. D., Two novel types of L-glutamate receptors with affinities for NMDA and L-cysteine in the olfactory organ of the Caribbean spiny lobster Panulirus argus, Brain Res., 111, 292, 1997. 

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