The Facts of Sex in Relation to Metabolism. 251 
(c) And, while every one recognises that there are two 
sets of vital processes—one of assimilation, construction, or 
synthesis; the other of disassimilation, dissipation, or 
analysis, when we come to consider these complementary 
sets of processes (conveniently termed anabolism and 
katabolism) we find that we do not know whether both 
are in the same sense activities dependent on stimuli 
(Hering), or whether anabolism is self-regulative, “e., 
autonomic (Gaskell). 
(d) Moreover, until we can trace in much greater detail 
than is at present possible whole series of chemical trans- 
formations, of which we have at present merely glimpses, we 
shall not be able to say with security that this or that 
- substance is an anastate or a katastate—a stage im a con- 
structive or in a disruptive process. For it is évident that a 
substance of some complexity might be either a step in the 
upward raising of food or a step in the disruption of highly 
complex material. 
In presence of so much uncertainty, it seems wise either 
to discard altogether such apparently precise terms as 
anabolism and katabolism, or to use them at present in a 
very wide sense, as wide as is consistent with utility. Let 
us illustrate the manner in which the terms may be used. 
Nothing is more characteristic of organisms than their 
power of growth, or their progressive accumulation of matter 
and energy. Now, when a cell or an organism continues for 
a time to feed well and to increase in size, remaining also 
quite healthy, it seems to us almost a truism to say that 
during this period of growth the processes of construction, of 
chemical synthesis, of accumulation of matter and energy, 
have been more rapid, and, on the whole, greater than those 
of disruption and expenditure. 
If we could measure in normal adult life the constructive 
or anabolic processes by which there is a storage of potential 
energy, and the disruptive or katabolic processes in which 
energy is expended, and if we express their relation during 
assimilation by the ratio = this ratio is greater than 
unity; while during the time that assimilation is not in 
