Temperature Is a Major FactorAffecting Tissue Function

Because body function is the result of chemical and physical processes that are sensitive to changes in temperature, animals use a variety Ofstrategies to regulate the temperature of their tissues. If body temperature is allowed to decrease too much below its normal value of about 38⁰C (~ 100^o F), metabolic processes are slowed to such an extent that body function ceases. Below 34^oC (93.2^o F), animals become unable to regu­late their own temperature, and at 27^o to 29^o C (80.6^o -84.2^o F), cardiac fibrillation and death occur. At the other extreme, an increase in temperature to 45^o C (113^o F) can cause fatal brain lesions.