58 FRANCIS O. SCHMITT 



lem may also be considered from the biological point of view. When in 

 the embryological sequence are the various structural proteins elabo- 

 rated? The embryologist can trace the steps in the differentiation of 

 the nervous system, muscles, connective tissue and so on, from the 

 earliest anlagen. But characteristic nerve fibers, myofibrils, and collagen 

 fibers are differentiated considerably after the tissue is determined. 

 When in these processes are the neuronin of nerve fibers, the myosin 

 and actin of muscle fibers, and the collagen of connective tissue elabo- 

 rated ? Are these fibrous proteins produced full blown or are they formed 

 from chemical "anlagen" or precursors? In other words, is there an 

 ontogeny of the structural proteins or are they formed under the in- 

 fluence of templates preexisting in the embryonic cells, possibly even 

 in the egg itself? 



These are large questions which have been mostly academic in the 

 past because the means did not exist by which they might be answered, 

 but it is now possible to make a beginning in such investigations. For 

 example, collagen fibrils can now be readily recognized in the electron 

 microscope. It should be possible therefore to examine embryonic 

 material at various stages of development to determine when and where 

 collagen fibrils first make their appearance. 



The technical aspects of the problem are by no means insurmountable 

 and will no doubt yield if a determined effort is made. The possibility 

 of laying the foundation for a new theoretical biology based on data 

 obtained at the molecular level is worthy of the best collaborative efforts 

 of biophysicists, biochemists and biologists. As the answers to these 

 problems are found, a clearer knowledge of the phenomena of growth, 

 normal and abnormal, must inevitably follow. 



Molecular Ecology 



The interaction of structural components with their environment is 

 at the basis of general and developmental physiology. Such interactions 

 depend not only on individual groups, such as particular amino acid side 

 chains, but on the molecular reacting system as a whole. Molecular 

 morphology should be studied not independent of or even consecutively 

 with the dynamic aspects, but simultaneously where possible. This 

 amounts to a study of molecular ecology, a term which I borrow from 

 Dr. Paul Weiss. 



In a sense this is implied in what has been said before. Thus certain 

 fibrous proteins react spectacularly to changes in their environment. 



