THE PHOTOSYNTHETIC PROCESS 63 



In conclusion, we may feel moderately certain that the secrets of 

 photosynthesis are revealed in their broader phases, although one 

 must ever keep in mind that the simple possible schemes worked 

 out in the light of our present physiological knowledge may not 

 be the real ones. Neither are those in vitro necessarily the ones 

 employed by the living plant. 



QUESTIONS 



1. Why is the formaldehyde produced in the process of photosynthesis not 

 poisonous to the plant? 



2. What are the present possibilities of producing food chemically? 



3. What is catalase? What is meant by in vitro? 



4. Using the equations of Baly, how many grams of glucose could be pro- 

 duced from a gram of carbon dioxide? How many grams of water would be 

 required? 



5. What is meant by condensation? polymerization? 



REFERENCES 



Baly, E. — Photosynthesis. Science, 68:364, 1928. 



Baly, E., Heilbron, I. M., and Barker, W. F. — Photosynthesis. J. Ind. 



Eng. Chem., 16:1016, 1924. 

 Baudisch, O. — The formation of organic compounds from inorganic by the 



influence of light. Science, 57:451, 1923. 

 Ewart, A. J. — On chlorophyll, carotin, and xanthophyll and the production 



of sugar from formaldehyde. Proc. Roy. Soc. Victoria, 30:178, 1918. 

 Gordon, R. B.— Suggested equations for the photosynthetic reaction. Ohio 



Jour. Sci., 29:131, 1929. 

 Heilbron, I. — The photosynthesis of plant products. Nature, 111:502, 1923. 

 P., J. — The first sugar in photosynthesis and the role of cane sugar in the 



plant, Nature, 127:634, 1931. 

 Spoehr, H. A. — The development of conceptions of photosynthesis since 



Ingen-Housz. Sci. Mo., 9:32, 1919. 

 Stiles, W.— Carbon assimilation. Sci. Prog., 19:392, 1925. 



Photosynthesis, Longmans, 1925. 



Modern views of the mechanism of carbon assimilation. Scientia, 



41:117, 1927. 



