GENERAL BIOLOGY 



C for 5-10 minutes. Pour solution into clean test tubes and (i) 

 examine color in transmitted and reflected light. (2) Focus light 

 into interior of tube with a lens and observe fluorescence. (3) 

 Wrap one tube in black paper, leave another unwrapped, and ex- 

 pose both to bright light to observe effect of light. (4) Note the 

 color of the leaves which were in alcohol. (5) Observe also color 

 of etiolated and variegated leaves of Coleus. (6) Class demon- 

 stration of spectroscopic lines of chlorophyll (Ganong's Physi- 

 ology, pp. 82-84). 

 , Record in your note book results of these experiments. 



b. Demonstration of effects of light on living leaves. 



1. Keep a potted bean plant in a dark room for a day or two, 

 and then expose to sunlight for 2 hours, having previously screened 

 a portion of one leaf with (a) a strip of lead foil. 



2. Remove screened leaves from plant, immerse in hot water, 

 and place in a flat dish of alcohol until white ; pour off alcohol and 

 cover leaves with a solution of iodine. 



Sketch leaves and explain results. 



(The leaves may be preserved afterwards in alcohol and devel- 

 oped again in iodine solution.) 



c. Demonstration of Source of C0 2 in Photosynthesis. 

 Remove two leaves with petioles, place cut ends of latter in small 



bottles of water and put one leaf in sealed jar containing soda 

 lime to absorb CO 2 , the other in sealed jar without soda lime; 

 expose both jars to sunlight for 2 hours and then treat both leaves 

 as in b (2). 



Record and explain results in your notes. 



d. Demonstration of Formation of 2 in Photosynthesis. 



1. Observe bubbles of gas escaping from a submerged water 

 plant (Cabomba, Elodea). 



2. Place supported funnel over plant and conduct bubbles into 

 test tube filled with water and held in inverted position in jar of 

 water. 



3. Test collected gas with phosphorus match or with glowing 

 match stick. 



Describe and explain results. 



2. SYNTHESIS OF PROTEINS. 



a. Demonstration of Source of Nitrogen. 



i. Compare the relative growth of seedling beans in (a) 



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