chambers dictionary of the unexplained illustration

#Chambers dictionary of the unexplained illustration skin#

In stage 2, body temperature drops by 2-4☌ (35-33 degrees).

For people in stage 1 hypethermia, body temperature drops by 1-2☌ below normal temperature (35-36☌). Hypothermia is a condition in which an organism's temperature drops below that required for normal metabolism and function. Other factors that can influence body temperature are age (infants and children have a wider range of body temperature than adults, and elderly have lower body temperatures than others) menstruation cycle in women (the temperature rises in the ovulatory midcycle and remains high until menses) and exercise (temperature rises with moderate to vigorous muscular activity). Elevation of temperature above normal is called fever (pyrexia), and subnormal temperature is hypothermia. Muscular work (including shivering) is a mechanism for raising body temperature.

#Chambers dictionary of the unexplained illustration skin#

Eighty-five percent of body heat is lost through the skin (radiation, conduction, sweating) and the remainder through the lungs and fecal and urinary excretions. Oral temperature measurement may be inaccurate if performed just after the patient has ingested cold or hot substances or has been breathing with an open mouth.īody temperature is regulated by thermoregulatory centers in the hypothalamus that balance heat production and heat loss. Rectal temperature is usually from 0.5° to 1.0☏ (0.28° to 0.56☌) higher than by mouth axillary temperature is about 0.5☏ (0.28☌) lower than by mouth. Body temperature may be measured by a placing a thermometer in the mouth, the rectum, under the arm, in the bladder, within the chambers of the heart, or in the external auditory canal of the ear. Daily fluctuations in an individual may be 1° or 2☏. Body temperature varies with the time of day and the site of measurement. When these vessels dilate, they allow more warm blood from the interior of the body to flow through them, where it is cooled by the surrounding air.Ī marker of endocrine, metabolic, or muscle activity the response of the body to heat or cold in the environment or the presence of infection, inflammation, among other illnesses it is one of the vital signs. The vessels of this system form a network just under the skin. This process is accelerated by panting.Īn important regulator of body heat is the peripheral capillary system. Heat is also eliminated by the evaporation of moisture in the lungs. Sweat is released from sweat glands beneath the skin, and as it evaporates, the skin is cooled. When the outside temperature goes up, the body's cooling system is ordered into action. Shivering is a form of this activity-a muscular reflex that produces heat. Another signal from the brain stimulates muscular activity, which releases heat. Sometimes it takes on a bluish color, the result of a color change in the blood, which occurs when the blood, flowing slowly, gives off more of its oxygen than usual. The arterioles constrict so that less blood will flow near the body's surface.

At the same time, the body acts to conserve its heat. This heat is conducted to the blood and distributed throughout the body. Certain cells of the hypothalamus then signal for an increase in the body's heat production. When the outside temperature drops, nerve endings near the skin surface sense the change and communicate it to the hypothalamus. To maintain a constant temperature, the body must be able to respond to changes in the temperature of its surroundings.