Re: what effect does temperature have on breathing rate?

John:  This is an involved question, but I will try & make a fairly 
straight forward answer.  As you probably realize, metabolism is dependant 
on many things, one of which is oxygen.  As the temperature goes up, either 
in an organism that is "warm" blooded, like us (as with a fever) or due to 
an outside rise in temp. (as with a "cold" blooded animal) whose body temp. 
actually changes due to the ambient temp., all of the metabolic reactions 
speed up.  This is due to the increase in molecular movement (increase in 
kinetic energy) & this causes a "need" for more oxygen to continue the 
aerobic respiratory reactions.  Since these are the reactions that power 
our bodies by making the majority of the ATP's, we begin to breath more 
rapidly.  There are receptors in the central nervous system that sense the 
increase in blood & interstitial fluid temp. & signal the respiratory 
centers in the medulla & pons to begin an increase in breathing rate.  
This helps our bodies to keep pace with its oxygen demands. In some aquatic 
animals, as the water temp. increases, their respiratory rate increases for 
the above reason as well as in order to obtain more oxygen because the 
water doesn't hold as much oxygen at a higher temp. (Pour a glass of warm 
water & observe the cloudiness.  That is from oxygen being dissapated from 
the water.) This is less true for us although it may play a part in VERY 
humid, hot weather.  I hope that my answer helps your understanding.  J. 
Bridger