Animals, cold-blooded

Morphine. This alkaloid exerts both a depressing and a stimulating action on the central nervous system, the depression affecting the brain especially the sensation of pain and the respiration the cerebral motoi functions are less affected. The stimulant action in the cord is best seen in the cold-blooded animals, when it may develop into tonic convulsions. In higher animals, but rarely in man, there may be some indication of this stimulant action. In cats it may also involve the motor areas, and they... 

Thehaine stands at the other end of the series from morphine and is a convulsant poison rather than a narcotic (see table, p. 261). Hildebrandt states that it excites the reflexes of cold-blooded animals but in dogs it exerts a narcotic and anti-emetic effect resembling that of morphine rather than that of chloromorphide. The alkaloid is scarcely used in medicine as such, but is a primary material for the preparation of certain of the modern morphine derivatives, such as hydroxydihj dro-codeinone and methyldihydromorphinor.e. 

Kalt-blelche, /. cold bleaching. -bUiter, m. cold-blooded animal, -bruch, m. cold-short ness. 

Cold-blooded animals decrease their body temperature in cold weather to match that of their environment. The activation energy of a certain reaction in a cold-blooded animal is 65 kj/mol. By what percentage is the rate of the reaction decreased if the body temperature of the animal drops from 35°C to 22°C ... 

Suggestions that phosphatic minerals in mammals could be used, however, revived the interest in climate reconstruction in continental interiors. Aquatic, cold-blooded animals like fish have body temperatures and body water oxygen isotopic compositions that are directly dependent on the water in which they live. For these animals, a commonly used equation describes the relationships among temperature, water oxygen isotopic composition and phosphate oxygen isotopic composition as (Longinelli and Nuti 1973 verified by Kolodny et al. 1983, among others) ... 

Wild and domestic animals, including mammals, birds, reptiles and insects, are likely to harbour enteric pathogens and are therefore potential transmitters to agricultural environments and produce. For instance, Salmonella spp. has been isolated from the intestinal tracts of most warm-blooded and many cold-blooded animals. 

The ability of some organisms to control the pH and temperature of their cells and tissues represents a major biological development. Homeothermic animals (e.g. mammals) maintain a constant temperature of about 37 °C as this corresponds to the temperature of optimum activity of most enzymes. Poikilothermic or so-called cold-blooded animals (e.g. reptiles) have to sun themselves for sometime every morning in order to raise their body temperature in order to optimize enzyme activity within their cells. 

By contrast, thermal pollution can have some significant effects on the natural ecosystem. As the temperature of water rises, its ability to hold dissolved oxygen declines. The graph shows how the solubility of oxygen varies with temperature. Since fish are cold-blooded animals, they are unable to regulate their own temperatures, and... 

A literature project. Until the 1960s, dinosaurs were thought to be cold-blooded animals, which means they could not regulate their body temperature. Reference 1 describes how the l8O/l60 ratio in dinosaur bones suggests that some species were warm blooded. Find reference 1, preferably at http //pubs.acs.org/ac if your institution has an electronic subscription to Analytical Chemistry. Explain how the 180/l60 ratio implies that an animal is warm or cold blooded. Explain the criteria that were used to determine the likelihood that l80/l60 in bone phosphate was altered after the dinosaur died. Describe how bone samples were prepared for analysis of oxygen isotopes and state the results of the measurements. 

Because molecules slow down with decreasing temperature, the rate at which neurotransmitters are able to diffuse across the synaptic cleft decreases with temperature. This is one of the reasons cold-blooded animals become sluggish at colder temperatures. As neurotransmitters take longer to diffuse across the synaptic cleft, the rate at which nerve signals can reach target muscles slows down. 

The most prominent biological feature of silatranes is the remarkable mammalian toxicity exhibited by their 1-aryl derivatives (Table 4). Some of them are several times more toxic than widely known poisons such as hydrocyanic acid and strychnine. At the same time 1-arylsilatranes are almost harmless for cold-blooded animals, plants, and microorganisms. For example, frogs are very resistant to 1-phenylsilatrane (9) doses of 30-40 mg/kg have no effect. 

The fourth compound—the most toxic—is lophopherine, which is extremely toxic to cold-blooded animals, and was approached very cautiously by Heffter in his evaluations. At 20 mg., he had quite a radical vaso-dilation and an immediate headache. He pursued it religiously up to 50 mg.—at which there was quite a drop in heart rate and a compensatory increase in blood pressure, but no mescaline-like central effects whatsoever, no visual effects and no interpretative effects akin to mescaline. 

Reptilia Snakes, lizards, alligators, dinosaurs, turtles Terrestrial cold-blooded animals with scaly skin, four legs, breathe only in air, some lay eggs, some give live birth... 

Most naturally occurring fats and oils are mixtures of triglycerides containing a variety of saturated and unsaturated fatty acids. Even the individual triglycerides are often mixed, containing two or three different fatty acids. In general, oils from plants and cold-blooded animals contain more unsaturations than fats from warm-blooded animals. Table 25-2 gives the approximate composition of the fatty acids obtained from hydrolysis of some common fats and oils. 

The first indication that copper is an essential body constituent, at least in some species, came with the recognition of the copper-containing respiratory pigment hemocyanin in cold-blooded animals (F8), and the discovery of turacin, a copper-containing pigment in the feathers of certain birds (CIO). 

Although methysticin had been isolated in 1860-61, no pharmacological evaluation of the kavalactones was available until Lewin published his admirable monograph (Lewin, 1886). However, since only limited quantities of methysticin and yangonin were at his disposal, his data must now be considered to be only of historical importance. Nonetheless, they are worth mentioning. Methysticin was found to be inactive when injected intra-peritoneally in doses of up to 2 g in both warm- and cold-blooded animals. Yangonin, available in even smaller quantities, was tested in only two frogs in oral doses of 0.05 g with no observable effects. 

For instance, the velocity of enzyme reactions is vary much dependent on temperature, If the temperature is raised, the initial reaction velocity increases (as is the case for all chemical reactions, which go faster at higher temperatures), but also the enzyme is less stable and sooner inactivated. Most mammalian enzymes work best at thirty-five to forty degrees Centigrade, the temperature at which the body is normally maintained, whilst fish and other cold-blooded animals often have enzymes which function well at lower temperatures. 

Also, all terrestrial insects are cold-blooded animals. 

Some solutes may cause inhibition, i.e., reduce growth at quite low concentrations. Several, generally polymeric, substances can adsorb onto ice crystals and thereby reduce the freezing rate. This includes many proteins. Especially the antifreeze peptides, found in many plants and cold-blooded animals that have been subjected to cold stress, strongly decrease growth rate at fairly low concentrations. The presence of solutes and particulate material can also affect the shape of the ice crystals. 

Replacement refers to efforts to engage alternatives to animal use. This includes the use of computer models, non-living tissues and cells and replacement of higher order animals (primates and mammals) with lower order animals (e.g. cold-blooded animals, invertebrates) or bacteria whenever possible. 

Getting Things Moving The metabolic processes of cold-blooded animals like this baby Nile crocodile (Crocodylus niloticus) speed up as the temperatures rise toward midday. In this chapter, you ll see how temperature, as well as several other factors, influences the speed of a reaction. 

Leven (191) was the first to observe an increase in the respiration rate in the frog and cold-blooded animals. 

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