Adaptation of the body to hot and cold - Essay Example

? Topic:  Adaptation of the body to hot and cold Introduction The human being’s adaptability to heat and cold is a phenomenon originated millions of years ago. Earth is a planet with extreme climatic conditions, and adaptation to it is the genetic quality imbedded in the physiology of human beings. Since ancient times, human beings have been surviving in hot and humid weather of Sahara and extreme cold weather of Antarctica. Much of the earth’s hot and cold places are inhabited by human beings. The important fact is that the body of the person is permitted to live in any harsh weather conditions. However, the body needs a supply of water, shade and limited physical activity in order for the human being to survive. According to Wenger (2009), “Problems due to heat stress may occur whenever the rate of heat production or heat gain from the environment is sufficiently large in relation to the body’s ability to dissipate heat.” In a human body, problems such as numbness and snow bite can occur in extreme cold weather. However, sudden adaptation to an extreme weather is not likely for the physiology of a human being. There is an extent to which people can survive in a harsh climatic condition. The adaptation to hot or cold weather for the human body is possible only through the conditioned genetic make of the body. Unfortunately, it is a fact that with the continuous exposure to hot or cold weather, the tissues of the human body get injured. The body has different mechanisms by which it can adapt to cold and hot weather conditions. However, if a person is exposed to extreme hot or cold directly, then he can famish in a short period of time. Body’s adaptability to heat The human body is designed to sustain at an average temperature level and the body also maintains an average temperature level of 37 degree centigrade. However, when we attempt to sustain in a temperature above that, then the body brings out its adaptation mechanisms. When our body gets hot, it starts a biological process called sweating in order to cool off the body. But when the heat of the environment gets hotter than that, the tissue of the body is injured. The heat can affect the protein’s biological processing and this can lead to complication in the health of the human being exposed to extreme heat. The change in the protein configuration of the cell is called “denaturation.” High temperature can alter the nature of protein or kill the cells. If a living cell is exposed to heat above 45 degrees, then burning of the skin occurs. The damage of the skin depends on the duration and intensity of the heat applied to the human body. We, human beings, like any other mammal, are “homeotherms”; in other words, warm blooded animals. The human body has the ability to maintain its temperature by different biological processing. The human body does not react negatively to any minor changes in temperature, whether it is hot or cold. The main method by which the body defends against the heat in the environment is by perspiration. By perspiration the body injects fluid into the surface of the skin to make it moist and cool. As per Dugdale (2012), “Sweating is the release of a salty liquid from the body's sweat glands. This process is also called perspiration.” The phenomenon of sweating The phenomenon of sweating is the only way in which the body reacts to the extreme hot weather conditions. In this biological process, body injects salty liquid on to the surface of skin with the aid of sweat glands. There are millions of sweat glands in a human body and this process of sweating, in other words, is called “perspiration.” Sweating is an extremely important activity of the body to stay cool in harsh environmental conditions. Sweat is mainly obvious on the palms of the hand, under the arm or under the feet. The quantity a person sweats depends on the amount of sweat glands a person possesses. The sweat glands of an individual are functional as one attains their puberty period. Although, women possess more sweat glands, men perspire more than women as their sweat glands are more active. As per Garrett (2000), “Acclimation studies have shown that elevated sweating rates are accompanied by a decrease in the concentration of sodium and chloride in sweat, in spite of the increased flow rate.” As the information suggests, excessive sweating can reduce sodium and chloride in the body and can trigger dehydration. However, in an increasingly hot weather the body gets dehydrated and human beings can fall into heat stress and collapse. It is a scientific fact that the cells and tissues of a human body can adapt to a minimum temperature of 10 degree centigrade to maximum 45 degree centigrade. After this point a human being can injure himself and even can step into a fatal stage. The body of an individual falls into two divisions called the warm internal core and the outer layer. The warm internal core normally maintains the average temperature in more sustainable weather conditions, while the outer layer of the body is exposed to harsh weather conditions. It is when the outer layer contacts with harsh heating conditions that it signals brain to produce sweat to keep the body cool. But this process is retained till the temperature outside remains below 45degrees centigrade. As per O’Neil (1998), “In extremely hot climates or as a result of uncontrollable infections, core body temperatures can raise to equally fatal levels.  This is called hyperthermia.” In the case of hyperthermia, the human body can slip into a fatal stage. Body’s adaptation ability to cold Similar to adaptation to heat, the body has adaptation to cold but in a different manner. Cold, in the same way as heat, has the ability to injure the tissue of the body, however by different mechanisms. Cold can damage cell through two mechanisms. First, the crystals of ice themselves object the cell membrane functioning. Second, the increase in the cytoplasm’s solute temperature leads to the denaturalization of protein by taking away the water of hydration. This kind of mechanism disrupts the functioning of cytoplasm and the life of the cell fails. Thus, when the human body is exposed to cold, the liquid present in the body crystallizes and blocks the functioning of the body and results in death of an individual. Like in hot weather, the body does not have enough capacity to survive in a cold temperature. The human body cannot survive in a temperature which is lower than 10 degrees centigrade without shivering. Moreover, in this kind of cold, body needs a protection in the form of warm clothing. Otherwise, the body starts to shiver and formulate numbness and snow bite. However, a person’s ability to cope with a cold climate also depends on his exposure to harsh cold weather previously. But it can be found that people living in extreme cold weather have genetic support from the body to remain at a static temperature. For example, the people in Antarctica live normally there, but if we tend to survive in that weather condition, death is for sure. Generally, the human body has certain mechanisms to maintain the body temperature in cold weather, known as “homeostasis.” The process of homeostasis The process of homeostasis is the main mechanism by which the body attempts to regulate the bodily temperature of a human being. The “homeostasis” is a process triggered by the body when it gets the message from the brain that the external environment of the body can damage its very own functioning. As per Hartney (2009),“Homeostasis is the process by which the body attempts to maintain a state of stable physiological balance.” In order to stay alive in a cold weather below 10 degrees centigrade, the body needs to step on to the homeostasis process. For instance, if one tries to remain in cold weather, then the body reacts by shivering. And this process is caused by homeostasis in order to keep the body warm. In homeostasis, the body, in order to remain at a normal temperature, sinks the capillaries into blood to extract heat from blood. Homeostasis has the literary meaning “same state” which means that the body remains in the same state as the external environmental conditions change. Body temperature control in inhuman body In the human body, there is consistently a need of body temperature regulation due to the human being’s exposure to varying climatic conditions. In the body the temperature regulating system is controlled by thermoregulatory centre situated in the hypothalamus. The thermoregulatory unit receives input from two parts of thermo receptors situated in the hypothalamus. The receptors in the hypothalamus have the ability to monitor the blood temperature while it passes through brain, which is the core temperature. Moreover, it has receptors in skin which pay vigilance to the external temperature. Both these sets of receptors are needed as the brain requires monitoring the external and internal temperature of the body. According to Stevenson (2002)), “The maintenance of body temperature or thermoregulation is a dynamic system: if heat loss is greater than heat production, then the core temperature drops. Likewise, if heat loss is less than heat production, then the core temperature rises.” Conclusion The body’s adaptation to heat and cold environment is regulated by various sensory organs in the human body. However, the body’s capability to adapt to a particular temperature depends slightly on the age and sex of a person. For instance, the body in the condition of heat produces sweat through sweat glands and in a cold climate produces shivering to warm up the body. As per Bindon (2002), “The sweat glands are innervated by the sympathetic nervous system; when a rise in core temperature is detected by the hypothalamus, impulses to the sympathetic system cause an increase in sweat output.” However, there is a limit for a body to adapt to hot or cold weather. In an environment with temperature above 45 degrees centigrade, the sweat production gets saturated and dehydration occurs. It is a scientific fact that the human body cannot survive above 45 degrees for a prolonged period and could famish. In general, human beings have an enormous capacity to adapt, biochemically, anatomically and physiologically, to various kinds of environmental conditions. And they also possess the technological provision to adjust the environmental condition according to his desire. However in the absence of technical and sophisticated facility, the human body needs to completely thrive on the biochemical and anatomical techniques of the body to survive. And the genuine fact is that in the absence of technological facilities, the human body cannot survive above 45 degrees centigrade and below 10 degrees centigrade for a long time. According to Taylor (2000), “Humans possess regulatory mechanisms that ensure the stability of the internal environment, with such stability being conducive to life and optimal physiological function.” Finally, it can be concluded that people who are genetically conditioned to any harsh climatic condition have more adaptability than normal people to hot and cold climate. References Bindon, J. (2002, August 20). Human adaptability. anthropology.ua.edu. Retrieved August 6, 2012, from http://anthropology.ua.edu/bindon/ant475/heatcold/thermo.htm. Dugdale, D. C. (2012). Sweating. nlm.nih.gov. A.D.A.M.Inc. Retrieved August 2, 2012, from . Garrett, W. E. (2000). Exercise and sport science (p. 416). Philadelphia: Lippincott William&Wilkins. Hartney, E. (2009, March 27). Definition of homeostasis. addictions.about.com. Retrieved August 5, 2012, from http://addictions.about.com/od/glossar1/g/defhomeostasis.htm. O'Neil, D. (1998). Adapting to climate extremes. anthro.palomar.edu. Retrieved August 4, 2012, from http://anthro.palomar.edu/adapt/adapt_2.htm. Stevenson, P. (2002, May 18). Australian Naturopathic Network. ann.com.au. Retrieved August 5, 2012, from http://www.ann.com.au/MedSci/rmoregul.htm. Taylor, N. A. (2000). Heat adaptation: Guidelines for the optimisation of human performance. .ismj.com. Retrieved August 5, 2012, from http://www.ismj.com/default. asp?pageID=854255817%20-%2029/03/2006%20-%20Rank:0 Wenger, B. (2009). Human adaptation to hot. US Army Research Institute of Environmental Medicine, 1. Read More