RELATIVE GROWTH 



231 



10- 



2 3 4 5 6 8 10"* 2 3 4 5 6 8 10= 



Body weight 9 



Fig. 33. Relative growth (postnatal) of some organs of man (c5). After Linzbach, 1955. 



exerted by musculature. If available glucose is used for heavy muscular work, 

 mitotic rate is reduced to such extent that it does not increase immediately even 

 after rest. The well-known influence of dietetic factors on tumor growth follows a 

 similar pattern. Cancer growth is often suppressed in a diet close to the minimiuTi 

 maintenance level. 



Competition for nutritional factors provides certainly a partial explanation 

 only. It illustrates, however, the general principle that every tissue apparently 

 has a specific capability of appropriating material, which is expressed by the 

 allometry constant and determines its relative growth. 



Experimental investigations of physiological competition were made by F. E. Lehmann 

 and coworkers. If, in the regeneration of legs in Xenopus, the available material is quantita- 



Literaiure p. 233 



