QUESTIONS 163 



The total excretion of nitrogen is increased and there is an 

 alteration in the distribution of nitrogen among the urinary 

 constituents. The ammonia, the uric acid, and the kreatinin 

 are increased while the urea is relatively decreased. Kreatin 

 may also make its appearance. 



During the first stage of fever, while the temperature is 

 rising, there is always an increased retention of heat. In most 

 cases the production of heat is also increased on an average 

 from 20 to 30 per cent. Evidence has been obtained that at 

 this stage the cutaneous vessels are constricted. It is most 

 probable that an increased and perverted metabolism is the 

 primary cause of the increased production of heat. Mandel 

 has shown that one of the purin bases (xanthin) causes fever 

 in monkeys, and that the purin bases in the urine are increased 

 both in infective and aseptic fevers. There is a constant rela- 

 tion between the height of the fever and the quantity of purin 

 bases excreted. Xanthin fever can be antagonized by salicy- 

 lates but not by antipyrin. 



QUESTIONS ON CHAPTER IX 



Define the terms homoiothermous and poikilothermous. 



Give the body temperature of man. 



In what ways does it vary? 



Where are the warmest and the coldest blood of the body to be found? 



What factors influence body temperature? 



What is the source of the energy of heat? 



What percentage of heat is directly formed from the chemical energy of 

 the food? 



What are direct and indirect calorimetry? 



Describe a calorimeter. 



Describe fully how the calorimetric equivalent is obtained. 



Why is it necessary to obtain the calorimetric equivalent in calorimetry? 



Explain in detail how the heat lost to the air is calculated. 



What is the specific heat of a body? 



Explain how the heat lost by evaporation of water is obtained. 



What organs are principally concerned in heat production? 



What subsidiary sources of heat are there? 



How much heat does the heart produce? 



Define thermogenesis, thermolysis, and thermotaxis. 



Discuss thermotaxis. 



What is the effect upon heat production when a muscle is separated from 

 the central nervous system? 



Discuss the phenomenon of shivering. 



What is the proof that thermogenic centres exist? 



What classes of thermogenic centres are there, and where are they 

 located? 



How is thermolysis brought about? 



Explain the postmortem rise of temperature. 



Discuss the chemical and physical regulation of body temperature. 



Discuss briefly the physiological aspects of fever. 



