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It is more important for core body temerature than for skin temperature to stay constant, because
a constant core temerature is required for sustanace of life. All physiological processes occurs at
optimum body temperature(37 degree centigrade). Other wise extreme variation of
environmental temperature would affect animal’s life.
Through several physiological and behavioural and hypothalmic activity body temerature is
regulated.
Temperature-Decreasing Mechanism - When the Body Is Too Hot
In response to increased temperature heat-sensitive neurons of hypothalamic preoptic area
increase their firing rate 2- to 10-fold.this results in vasodilatation and increased rate of heat
transfer and profuse sweating. And it also causes decreased heat production by metabolism.
Temperature-Increasing Mechanisms- When the Body Is Too Cold:
In response to cold hypothalamic cold-sensitive neurons, increase their firing rate which causes
vasoconstriction, pilo erection and thermogenesis that increase body temperature. Through
chemical thermogenesis, epinephrine, nor-epinephrine is utilized to increase metabolic rate.
The body get rid of carbon dioxide through release of CO2 through expiration and excretion of
excess CO2 through kidney in the form of bicarbonate.
CO2 + H2O HCO3- + H
+
This equation maintains the body’s pH. When carbon dioxide increases in the cells it reacts with
water and form H+ and bicarbonate (HCO3 ) ions. H+ ions excrete through the urine as acid and
bicarbonates are reabsorbed through the renal tubule and then in capillari blood and acts as a
buffer in the cellular fluids.
Carbon dioxide causes acidosis. Because it reacts with water and form hydrogen ions, which
decreases the pH of body fluid and blood.
During exercise cellular metabolism increases that utilize oxygen as a result, oxygen
concentration decreases in tussues and oxygen requirement increases.
As metabolic rate increases during exercise, there is increased break down of foods, which
creates energy as well as metabolic end product which include heat, water and carbon dioxide.
Thus, during exercise carbon dioxide concentration increases. As carbon dioxide concentration
increases, body need to expell this carbon dioxide which occurs through...