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English
Biochemistry, general
Neurosciences
Yi** **
Chapter
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Chapter
Male and Female — Young and Old
As far as we can tell at present, no appreciable racial differences in olfactory acuity exist nor are there marked unacquired differences between normal persons and those, otherwise normal but deprived of sens...
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Concluding Note
It may possibly be thought strange that more has not been said in this book about the modern, very powerful techniques — various forms of chromatography and spectrometry, for example — now being increasingly a...
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Historical
Perhaps the first treatise on odours is that of Theophrastus who wrote his Concerning Odours in the second or third century B.C. He maintains that odours “are due to mixture for anything which is uncompounded has...
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Wheresoever the Carcase Is
The olfactory powers of dogs are not disputed — not so those of birds1. When Audubon “contradicted all former opinions on the subject” in Edinburgh in 1826, he did so with uneasy feelings expecting to encounter v...
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Savage and Blind
There is a widespread belief that primitive peoples and blind persons (or, at least, persons born blind or blinded while young) naturally have a particularly acute sense of smell. Some travellers have even cla...
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The Brave Smell of a Stone
Since it seems certain that volatile material only can be smelled, an explanation must be found for the fact that many non-volatile substances undoubtedly appear to emit odour. It is said, for example, that so...
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Some Curiosities
Robert Boyle’s gloves were not the only historical objects which were remarkable for the tenacity with which they retained their odour. There were also, for example, the documents of Albrecht von Haller (1708–...
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Introduction
How long a period of time has elapsed since the primate stock substituted sight for smell as the dominant sense we do not know, but it is certainly a very long time. Some investigators believe that this substi...
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Dog’s Life
The olfactory powers of some animals have naturally attracted considerable, if usually casual, attention and scientific studies of olfaction in various species have been conducted from time to time. Accurate o...
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Fishes that Tipple in the Deep
Mammals living in water (e. g., dolphins, porpoises, seals, walruses, whales) have poorly developed olfactory organs and are said, although the evidence appears to be scanty, to have an extremely poor sense of sm...
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Law and Order
Although the Weber-Fechner law, namely the rule that the increase of stimulus required to produce a just appreciable increase (the “just noticeable difference”) in sensation must always bear the same ratio to ...
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Physiological Mystery
The theories of olfaction have certainly been incomplete and rather unsatisfactory. Some of them are largely speculative. Others are philosophical, dealing with perception rather than sensation. But it is no long...
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Chapter and Conference Paper
Metarhodopsin III
The photic isomerization of rhodopsin is followed by a number of dark reactions (1) some of which are also photosensitive (2). Information is available on their various half- lifes, which, as expected, vary wi...
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Chapter and Conference Paper
Interrelations of Visual Pigments and “Vitamins A” in Fish and Amphibia
In frogs and fish, although perhaps not in mammals (1, 2), the pigment epithelium plays a decisive role in visual pigment regeneration (see Baumann, 3, for review). This is illustrated in Fig. 1 for Rana clamitan...
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Chapter and Conference Paper
Active Site and Enzymological Studies on the Components of the Visual Cycle
Developments in the biochemistry of vision over the last quarter century may be summarized by the equations 1–3 of Scheme 1. The first reaction in the Scheme involves the combination in a dark reaction of the ...
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Chapter and Conference Paper
Behavior of Rhodopsin and Metarhodopsin in Isolated Rhabdoms of Crabs and Lobster
The photoreceptor organelles — the rhabdoms — of decapod Crustacea are elongate structures consisting of interleaved layers of microvilli from seven or eight retinular cells (1,2,3). When the eyes are broken o...
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Chapter and Conference Paper
Biochemical Properties of Retinochrome
The cephalopod retina has two kinds of photosensitive pigments. These pigments have been examined in various squids and octopi (1–4), and are called rhodopsin and retinochrome(5). Rhodopsin is present in the o...
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Chapter and Conference Paper
The Photopigments in an Insect Retina
Colour vision is not an exclusive property of vertebrates. Also insects can discriminate wavelengths. The best known example is the honeybee, as shown by training experiments (1) and electrophysiological recor...
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Chapter and Conference Paper
Rod Dark-Adaptation and Visual Pigment Photoproducts
Measurement of the dark-adaptation of single retinal units (ganglion cells) in the frog has shown that the rod branch of the dark-adaptation curve after bleaching small amounts of rhodopsin is approximately ex...
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Chapter and Conference Paper
Adaptation Properties of Intracellularly Recorded Gekko Photoreceptor Potentials
Over the past century, a comprehensive description of the phenomena of visual adaptation in vertebrates has been achieved. More recently, much interest has focused on the identification of the cellular locus o...
