Listening In nature, warm-blooded animals such as mammals and birds need to keep their internal temperatures within a certain range. For most mammals this range is from about 36 to 38 degrees Celsius. Thermoregulation is responsible for maintaining this i

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In nature, warm-blooded animals such as mammals and birds need to keep their internal temperatures within a certain range. For most mammals this range is from about 36 to 38 degrees Celsius. Thermoregulation is responsible for maintaining this internal temperature regardless of whether the surrounding environment is much colder or warmer. Today we’ll discuss two important forms of thermoregulation that animals use to keep their internal body temperatures constant.

One form results from the insulating power of fat. When the temperature of the environment is colder than the animals’ internal temperature, the animal must counteract heat loss; that is, internal heat lost to the external environment. Most animals help prevent this heat loss by having a layer of fat present underneath the skin. This layer of fat prevents too much heat from escaping into the environment, helping to maintain the animals’ internal body temperature. For example, marine mammals such as whales have a very thick layer of insulation fat called blubber, just under the skin. This blubber insulation is so effective that these marine mammals maintain body core temperatures of about 36-38 degrees Celsius even when surrounded by much colder waters.

Another form of thermoregulation is evaporative cooling. When the external temperature is higher than the animals’ desired internal temperature, the animal uses this form of thermoregulation to battle against too much heat gain from its surrounding environment. They prevent overheating through the use evaporative cooling. You see, when water evaporates from a surface, the surface is cooled. For example, rodents need to keep an internal body temperature close to 40 degrees Celsius. And, at times, their surrounding environment can reach temperatures of up to 50 degrees. When this happens, Rodents will begin licking themselves and spreading their saliva across their bodies. As the saliva evaporates, the rodents are cooled, helping to keep their internal body temperatures constant.

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2014-04-10 Ekhlass1980 80.00 Check this speaking
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