THE ORGANIC CELL 
29 
the cell, as well as the work of physiological chemists on the 
staining reactions of the nuclein series, show clearly that the 
substance known as nucleinic acid (which is very rich in 
phosphorus) plays the most important part in the constructive 
process. 
It is extremely interesting to note that during the vegetative 
state of the cell the nucleinic acid is combined with a large 
amount of the albumin radicles to form nuclein. During the 
reproductive or mitotic stages of cell activity the combination 
breaks down, to a large extent leaving the chromosomes with 
a very high percentage of nucleinic acid, as shown by analysis 
of the head of a spermatozoon. It is strongly probable that 
this is the most important element passed on from cell to cell, 
and is very possibly the essential factor in the synthetic process 
of the nucleus, and indirectly with those of the cytoplasm. 
It must be remembered that the constructive metabolism 
exhibited by the nucleus is closely related to its function of 
morphological synthesis, and thus with inheritance. As a 
proof of this we have experiments on unicellular plants and 
animals, which go to show that the power of redeveloping lost 
parts is lost when the nucleus is removed, though the portion 
from which the nucleus has been removed may still show vital 
phenomena for a limited period, due to its inherent faculty 
of destructive metabolism. There is little doubt that the 
chromatin factor of the nucleus is the most important substance 
in the process of inheritance. This is shown very clearly by the 
fact that the germ and sperm nuclei are, by an exceedingly 
complicated and elaborate process, involving the evolution of a 
large amount of energy, prepared for their subsequent union, 
by which equal numbers of chromosomes are brought together 
from either sex. During fertilization these elements come 
together, and by a process of indirect division are exactly 
distributed to the resulting cells. That the nucleus is the 
essential factor in inheritance is further shown by the fact that 
the spermatozoon (which is practically all head, i.e. nucleus) 
supplies an amount of cytoplasm which is so small as to be 
almost negligible. From a broad analysis of the subject it 
seems evident that the nucleus is the great determining factor 
in the life and organisation of the cell ; and that it contains the 
