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EarAn ear is an organ used by an animal to detect sound. The term may refer to the entire system responsible for collection and processing of sound (the auditory system[?]), or merely the externally-visible part. Problems with the ear or auditory processing system in the brain can lead to deafness.
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Reptilian ears only have one bone - the stapes. The other two, unique to mammals, are derived from bones of the jaw, and allow finer detection of sound.
The middle ear is hollow. If the animal moves to a high-altitude environment, or dives into the water, there will be a pressure difference between the middle ear and the outside environment. This pressure will pose a risk of bursting or otherwise damaging the tympanum if it isn't relieved. This is the function of the Eustachian tubes - evolutionary descendants of the gills - which connect the middle ear to the nasal cavity[?]. The Eustachian tubes are normally pinched off at the nose end, to prevent being clogged with phlegm[?], but they may be opened by lowering and protruding the jaw.
The cochlea is a hollow organ filled with a fluid called endolymph[?] and lined on the inside with hair cells[?] - sensory cells which are topped with hair-like structures, the stereocilia[?]. All vibrations passing through the middle ear enter the endolymph. Hair cells are varied in length, so that they resonate with sounds of various frequency. Whenever a hair cell resonates, it sends a nerve impulse to the brain, which is perceived as a sound of whatever pitch the hair cell is associated with. A very strong movement of the endolymph due to very loud noise may cause hair cells to die. This is a common cause of partial hearing loss, and the reason why anyone near guns or heavy machinery should wear earmuffs[?] or earplugs[?].
The vestibular apparatus is filled with the same endolymph as the cochlea, but instead of detecting sound, it detects rotation of the head. If a line is drawn through the middle of each of the three semicircular canals, perpendicular to the plane in which the canal lies, the three lines would be perpendicular. They would represent three axes of rotation. Any rotation could be represented as three simultaneous rotations about the three axes.
See also:
It is cited by Dr. Lightfoot, Talmud, Hierosol, in Taanith, fol.
Eighty thousand priests were slain for the blood.html">blood.html">blood.html">blood.html">blood.html">blood.html">blood.html">blood of Zacharias. Rabbi
woman's court.html">court.html">court, or in the court of Israel? He answered, Neither in the
priests; and they did not treat his blood in the same manner as they were
written, He shall pour out his blood, and cover it with dust. But it is
of a rock.html">rock; she poured it not upon the ground. (Ezek. xxiv. 7.) But why
set his blood upon the top of a rock, that it should not be covered.
and a king; they shed the blood of the innocent they polluted the court:
Nebuzaradan came there (viz. to Jerusalem,) he saw his blood bubbling,
calves, lambs, and rams, which we have offered upon the altar. He
said I will try whether this be their blood: accordingly they brought
these did not bubble. Then he said, Declare to me the truth of this
him, He was a priest, prophet, and judge, who prophesied to Israel all
him, and slew him. Then, said he, I will appease him then he took the
yet appeased. Next he took the young boys from the schools, and slew them
slew them in the-same place, and yet it still bubbled. So he slew at
cease bubbling, then he drew near to it, and said, O Zacharias,
countrymen, shall I slay them all? then the blood ceased, and did bubble
REFERENCES TO THE PROTEVANGELION.
[This Gospel is ascribed to James. The allusions to it in the ancient
obtained a very general credit in the Christian world. The controversies
Christ, and to his being a widower with children, before his.
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