The Origin of Life 21 

 REFERENCES 



Calvin, M. 1959. Round trip from space. Evolution 13: 362-377. A good 

 brief discussion of the problem of the origin of life. 



Miller, S. L. 1951. The formation of organic compounds on the primitive 

 earth. Ann. N.Y. Acad. Sci. 59: 260-275. See this for details on the 

 atmosphere experiment. This article is in a number entitled Modern 

 Ideas on Spontaneous Generation which contains several interesting 

 papers. 



Needham, A. E. 1959. The origination of life. Quart. Rev. Biol. 34: 189- 

 209. A stimulating discussion in very broad terms. 



Oparin, A. I., A. E. Braunshtein, A. G. Pasynskii, and T. E. Pavlovskaya 

 [eds.]. 1959. The Origin of Life on the Earth. Pergamon Press, New 

 York. This symposium volume contains a large number of important 

 papers, most of which are highly technical. 



Oparin, A. I. 1961. Life: Its Nature, Origin and Development. Academic, 

 New York. The latest revision of the classic work on the origin of life. 



Sagan, Carl. 1961. On the origin and planetary distribution of life. Radia- 

 tion Res. 15: 174-192. A recent summary paper with extensive 

 bibliography. 



Fig. 1.5 I ( see opposite page ) Diagrammatic theoretical representation 

 of the process of protein synthesis under the control of messenger RNA. 

 (1) ATP molecule. (2) Amino acid (tryptophan). (3) Enzyme medi- 

 ating high-energy bonding of tryptophan residue with adenylic acid 

 ( AMP ) . ( 4 ) Phosphate groups previously bonded with AMP dropping 

 away from enzyme substrate. ( 5 ) Same enzyme mediating transfer 

 of tryptophan residue and high-energy bond from AMP to proper transfer 

 RNA molecule. (6) AMP molecule dropping away from enzyme. (7) 

 Glycine-charged transfer RNA unit dropping away from glycine- 

 activating enzyme. (8) Messenger RNA template. (9) Start of synthesis 

 of protein strand. "Capital" methionine-charged transfer RNA unit 

 aligned with "capital" methionine triplet ( UAG ) on RNA template. 

 ( 10) "Lowercase" methionine-charged transfer RNA unit approaching 

 "lowercase" methionine triplet ( UGA ) on template. ( 11 ) Enzyme 

 "zipper" which assembles amino acid residues into protein. ( 12 ) Newly 

 tormed protein that has dropped away from template, freeing the 

 transfer RNA units involved in its synthesis. Only a small sample of 

 presumably many simultaneous reactions is shown in this diagram. 



