. Animal biology. Zoology; Biology. Olfactory cell Ethmoidaf cells Olfactory membrane. Palate „ ? c Posterior Opening of ^^^^^ eustachian ^"^^^ tube Nerve fibers Palate Nasal septum B Supporting cell Anterior pares Michelle and lower turbinates A Fig. 219.—Olfactory organ in man. A, view of side wall of the nasal cavity to show distribution of olfactory epithelium. Probes are passed through the passages leading to the frontal sinus, the sphenoidal , and the antrum in the cheek bone, all of which may be infected from the nose. Olfactory membrane stippled. B, vertical section, made on
. Animal biology. Zoology; Biology. Olfactory cell Ethmoidaf cells Olfactory membrane. Palate „ ? c Posterior Opening of ^^^^^ eustachian ^"^^^ tube Nerve fibers Palate Nasal septum B Supporting cell Anterior pares Michelle and lower turbinates A Fig. 219.—Olfactory organ in man. A, view of side wall of the nasal cavity to show distribution of olfactory epithelium. Probes are passed through the passages leading to the frontal sinus, the sphenoidal , and the antrum in the cheek bone, all of which may be infected from the nose. Olfactory membrane stippled. B, vertical section, made on line ab in Fig. A, showing the nasal cavity of one side, with the nasal septum. A probe is passed through the passage to the antrum. Olfactory membrane black. C, section of a portion of the olfactory mucous membrane; highly magnified. A variety of tactile organs is found in various vertebrates and on different parts of the body, but they share a common plan. Nerve end- ings occur between epithelial cells, and the impulses are produced by the mechanical stimulation due to pressure upon these delicate endings. The lateral line organs, which are found along the sides of the bodies and about the heads of some aquatic vertebrates, have for a long time puzzled zoologists and have had attributed to them various functions. Recent investigations by Parker, however, seem to show that these are stimulated by vibrations in the water of too great wave length and too little frequency to cause sensations of sound and that they give to the animal information concerning movements in the water which are important in the securing of food, the avoidance of enemies, and adjustment to currents. The most important organs of smell (Fig. 219) consist of sheets of sensory epithelial cells situated in the nasal pas- sages. Substances carried through the air in the form of fine particles fall upon this sensory epithelium and are dissolved in the fluid secreted on its surface. The cells are stimulated
Size: 1504px × 1661px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookcoll, booksubjectbiology, booksubjectzoology
