296 W H AT IS LIFE 



ing a molecular weight of 1213 has been built up 

 by the German chemist Emil Fischer. This is the 

 largest molecule ever produced by synthetic meth- 

 ods. The polypeptides synthesized by Fischer, 

 according to E. J. Holmyard, are very similar to 

 the first decomposition product of the proteins, the 

 peptones. C. W. Porter says that "no doubt this 

 compound would have been classed as a protein if 

 it had been discovered in nature instead of appearing 

 as a synthetic preparation." See Chemical Action 

 and Molecular Weight. 



Molecule. Physics. The structural unit in the 

 kinetic theory. To the alteration of the position or 

 relation of molecules all physical changes (freezing, 

 evaporation, etc.), as distinguished from chemical 

 changes, are due. 



Neoplasm. A new growth resulting from a patho- 

 logical condition. 



Nereis. A sea-worm. 



Nulvalent. Without chemical combining power. 

 The rare gases are nulvalent. 



Ooplasm. The cytoplasm of the Qgg\ i.e., the 

 protoplasm of the egg as distinguished from the egg- 

 nucleus. 



Osmotic Pressure. See Pressure, Osmotic. 



Oxidation. The process or state of the chemical 

 combination of an element or compound with 

 oxygen. Several types of reactions are covered by 

 this term. Oxygen enters into chemical combination 

 with most elements. 



Paleontology. The branch of biology that treats 

 of fossil plants and animals. 



Panspermia {Cosmozoa)^ Hijpothesis of. The hy- 

 pothesis that life-giving seeds are drifting about in 

 space. They encounter the planets, and fill their 

 surfaces with life as soon as the necessary conditions 



