Adaptions in Ectothermic and Endothermic Animals to Extreme Climates
First of all we need to understand what ectothermic and endothermic animals are.
Animals differ in their abilities to regulate body temperature (thermoregulation). We sometimes use the terms "cold-blooded" or "warm-blooded." Most reptiles feel cold to the touch, while mammals and birds often feel warm.
Somewhat more precise descriptions can be made by using the terms poikilothermic and homoiothermic. The body temperature of poikllotherms is relatively variable, while that of homeotherms is relatively constant.
Even more useful terms are Ectothermic or Endothermic, which suggest two different mechanisms of thermoregulation. Ectotherms generally obtain heat from their external surroundings. Their body temperature varies, corresponding at any time with the temperature of their external environment.
Endothermic animals, on the other hand, have relatively constant body temperatures. Their body temperature is independent of that of their external environment. Monkeys and walruses, for example, both have body temperatures of about 38„aC, despite living in very different habitats.
However if body temperature rises above its optimum level (usually around 40„aC in mammals) then the enzyme rate inside the body will go into sharp decline. This is because enzymes are proteins, and become denatured. One of the first organs to be affected is the brain. Since the brain controls breathing and the circulation, the rise in body temperature disrupts the normal functioning of these important systems.
If the body temperature decreases dramatically (hypothermia) then this will slow metabolic activity and impairs brain function.
Here is a graph to show the relationsh...
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...ightly to allow some air to pass underneath it. Snakes can regulate their temperature by placing different proportions of their bodies in sun or in shade. The variations are numerous, but the end result is the same ¡V some degree of temperature regulation in reptiles.
In conclusion the animals which exist in the extreme climates of the world have adapted to be able to live well in these habitats and will probably stay living in these habitats for a long time to come.
Bibliography:
Bibliography
Books: Biology, Principles and processes
By Michael Roberts, Michael Reiss, Grace Monger
Life on earth and Life in the freezer
By David Attenborough
Hutchinsons Encyclopedia
Video: BBC Biological science-Endotherms and Ectotherms
Multimedia: Encarta 97 Encyclopedia
Internet: WWW.educationalimages.com
WWW.wildlifeonone.com
There are numerous risks for a patient during the preoperative stage of the perioperative journey. All patients undergoing a surgical procedure are at risk of developing perioperative hypothermia, although there are various factors which also further increase an individual’s susceptibility (Burger & Fitzpatrick, 2009). An individual’s body type can cause them more susceptible to heat loss during the perioperative period. The patient’s nutritional state and being malnourished, if the individual is female and is of low body weight therefore a high ratio of body surface area to weight and limited insulation to prevent heat loss, these are all factors which negatively affect heat loss and therefore increasing the individual’s risk of perioperative hypothermia (Lynch et al.,
As humans are homeothermic mammals, core temperature is maintained within a narrow range, usually within 0.2° of 37°C regardless of the environment. This is a life saving adaptation since various physiological systems in the body require narrow temperature ranges in which they can function optimally.
After results, it was concluded that isopods prefer normal temperature conditions over warm conditions. We created these environments by adding water onto filter papers with the accounted for temperature measurements. The reason for the results could be seen in a usual isopod environment, it is usually dark, fresh, and moist, and the normal water temperature being the closest to that was the reason for their choosing. The Isopods seemed to locate the appropriate environment by the use of their antennas. For the investigation the normal water and warm water temperatures were independent variables. The observations were the control. The isopods behavior served as the dependent variables. The isopod behavior would be classified as movement in response to a cooler temperature environment taxis. All in all the hypothesis, “If the isopods are exposed to normal and warm temperatures then the normal temperature will be preferred” proved to be
The differences are due to the differences in environment, habits, size etc. One example is the fact that minks and humans both have lugs of similar shape but different lobes. Each of these similarities and/or differences benefit both the human and the mink, in their own unique way, with each structure having its own function. Overall, the mink is a very complex animal and so is an individual.
Metabolic rate is directly linked to the core temperature in an animal. An ectotherm, or cold blooded animal, warms its body mainly by absorbing heat from its surroundings. The amount of heat it derives from its metabolism is negligible. In contrast, endotherms derive most or all of its body heat from its own metabolism (Campbells,p899). Because ectotherms do not produce their own heat, they cannot actively ensure their ideal temperature for an ideal metabolic rate (aquacult.htp).
The body has specific ways of controlling the internal temperature: if the body is too cold then involuntary shivering occurs this causes the skeletal muscles to contract therefore producing heat. When conscious movement occurs the muscles again contract and relax which generate heat to warm the body up. Another way the body increases the temperature unconsciously the hairs all over the body stand on end causing a layer of air to be trapped, which acts like an insulator. When the body is too warm sweat is produced from pores in the skin, as this liquid sits on the skin it slowly evaporates causing the body temperature to drop, however if ...
In cold water submersion, the main response was the initiation of the bradycardia reflex promptly after face submersion. The heart rate as indicated in figure 3 showed a significant decrease in levels. These results are shown to be as expected in relation to the bradycardia reflex (2). In fig 5, Cardiac output shows the same trend in relation to heart rate from fig 3, as heart rate slows down approximately 32% (fig 3). Total peripheral resistance was increased in fig 2, this is so that more oxygen can be improved for the vital organs. The increased levels of total peripheral resistance is also to allow more of the blood ...
Although the AWA covers animals that are “warm-blooded” since 1972 the USDA does not include rats, mice, or birds to this list. It’s unfair for the rodents and birds to be excluded, because they are warm-blooded, and they are the two most used animals for animal experimentation. (Monamy)
Although the experiment produced varying results amongst the pairs of test tubes in each of the water temperatures, the Mean calculations proves that the temperature rising will increase the amount of kinetic energy in the movement of the Phosphate and Lipids in the cell membrane as well as breaking the hydrogen bonds of the proteins in the cell membrane,
"Life in the Polar Regions: Animals, Plants, and Others in Extreme Environments." Windows to the Universe. 12 Nov. 2010. Web. 07 Mar. 2011. .
Most warm-blooded predators like the lion have to hunt frequently while however, cold-blooded predators like crocodiles can go for days to even months between meals (Carnivores. n.d.).
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They have water-repellent fur to keep their warm, webbed feet, and ears and nostrils that close
In The Genetic Theory of Adaptation: A Brief History by H. Allen Orr the article discusses adaptation and how it was affected by micromutationism, phenotypic evolution, and sequence evolution and various models that arose through the years. Prior to getting into detail the article explains that “adaptation is not natural selection,” as emphasized in the 1930s by Ronald A. Fisher (Orr 1). It glosses over how evolutionary geneticists define and distinguish between the two terms and how the recent models on adaptation characterize evolutional patterns and fitness.
The ecological consequences of global climate change are expected to be drastic although not much is known as to how individual species will react to these changes. Irrespective of the causes of climate change, whether anthropogenic or natural, it is imperative that we address these concerns, as they will have widespread impacts on the human species, both directly and indirectly through forcings on other species. The climate is not expected to shift evenly and the ways in which certain species adapt or migrate due to these changes could be erratic and unpredictable. The rate at which the earth’s climate is currently changing is unprecedented and has not been seen in the past 450,000 years. Although many species have simply migrated northward or vertically up mountainsides to escape warming habitats, others do not have this luxury or cannot migrate fast enough to survive. The earth’s temperature has risen by over one degree Fahrenheit over the past century, based on land and sea level measurements. The temperature is expected to continue rising at a faster pace over the next century, possibly increasing by as much as seven degrees Celsius. In comparison, the earth’s average global temperature was only twelve degrees cooler than it is now during the last great ice age. A vast majority of species now living do so within a narrow spectrum of temperature ranges and will not be able to adapt to a warming climate on such a large scale. If humans are the cause of a warming climate we will ultimately be responsible for the destruction of millions of species.