Water is important roles to the survival of mankind. In general people might lack water about 3-5 days if more than that people could have died because water is. In human body generally water has essential function as below :
- Regulates body temperature.
- Moistens tissues such as those in the mouth, eyes and nose.
- Lubricates joints.
- Protects body organs and tissues.
- Helps prevent constipation.
- Lessens the burden on the kidneys and liver by flushing out waste products.
- Helps dissolve minerals and other nutrients to make the accessible to the body.
- Carries nutrients and oxygen to cells.
In this article, function water to regulates body temperature will explained further.
Water to Regulates Body Temperature.
In ordinary activity, metabolism in human body depends on heat loss by evaporation from body surface, radiation heat exchange, radiation from temperature of environment and heat stored in the body. In condition where heat stored equal to zero it is means that body temperature in normal condition, where heat stored negative body temperature will be increases and body temperature will be decreases in heat stored positive.
Figure 1. Heat transfer in human body .The body temperature of healthy person in normal conditions around 36-38oC . The body temperature varies depending on the activity and the state of the environment, lower temperatures in the morning and higher temperatures in the afternoon and evening. But the changes in body temperature at normal body is not significant around 0.5oC. The human body will be disturbed if there are in low or high than normal temperatures. In condition of the body temperature below 35oC then person suffering hypothermia, under 33oC suffering unconsciousness and on more serious level body can a coma at temperatures below 28oC . as well at high temperatures, hyperthermia, human brain and heart can be damage if the body temperatures more than 42oC.
Hyperthermia can caused by internal factor such as: consumption drugs, heat stroke and also caused by external factor such as: extreme environment temperature, body personal protective equipments for example people who working in industry, the military and first responders.
Water has an important role in regulating the temperatures stability in human body, especially when the body is experiencing hyperthermia. Figure 2 described the mechanism of the human body to prevent hypertermia and how water plays a role in that process.
Steps to prevent hypertermia as below:
- Increased blood and internal temperature.
- Impulse go to hypothalamus.
- Vasodilation occurs in skin blood vessies so more heat is lost cross skin.
- Sweat glands become more active, increasing evaporative heat loss.
- Body temperature decreases.
The hypothalamus acts as a receptor in regulation of human body temperature, by detecting fluctuations in temperature. The first environment temperature changes will received by the skin that serves as thermoreceptor, then this temperature change will be responded by hypothalamus. After that hypothalamus commanding body to make perspiration.
Perspiration presents the most effective mechanism of heat generation or output under physical work in high temperature. Through perspiration the body loses up to 80 % of its heat while under resting condition it is mere 10%. It is the only way of heat output in situations where the temperature of the environment is higher than body temperature. Perspiration mechanism shown in Figure 3. Sweat is produced by the sweat glands from plasma filtration. There are about 2.5 mil sweat glands in human body, about 200/1 mm2 on a palm and 10-20/1mm2. Sweat is mostly formed by water, ions (Na+,K+ and Cl-), lactic acid and urea. Under work in environment that has high temperature the body may lose up to 1 litre of sweat perhour per 1m2 of the body surface. Unless liquid losses are not sufficiently compensated, dehydration may occur and basic life functions may be jeopardized.
Water has main function to cooling body temperature in hyperthermia conditions, through perspiration. In case the temperature of environment increase that effect to increasing body temperature and then hyperthermia. Can imagined brain and heart will be damaged easily without water in human body.
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