CHAPTER II. GERMINATION AND GROWTH 

 I. PROCESSES ACCOMPANYING GERMINATION 



MATERIAL. A pint or two of corn, peas, beans, or any quickly germi- 

 nating seed. 



APPLIANCES. Matches ; wood splinters ; gas jet or alcohol lamp ; 

 test tubes ; a small quantity of mercuric oxide ; a thermometer ; a couple 

 of two-quart preserve jars, and a smaller wide-mouthed bottle that can 

 be put into one of them ; some limewater ; a glass tube (the straws used 

 by druggists for soft drinks will answer). 



26. Preliminary exercises. Before taking up the study 

 of germinating seeds, it is important to learn from what 

 sources the organic substances used by the growing plant 

 are derived, and some of the processes that accompany 

 growth and development. 



EXPERIMENT 21. To SHOW THE CHANGES THAT ACCOMPANY OXIDA- 

 TION. Strike a match and let it burn out. Examine the burnt portion 

 remaining in your hand ; what changes do you notice ? These changes 

 have been caused by the union of some substance in the match with 

 something outside of it, in the act of burning ; let us see if we can find 

 out what this outside substance is. 



EXPERIMENT 22. To SHOW THE ACTIVE AGENT IN OXIDATION. - 

 Heat some mercuric oxide in a test tube over the flame of a burner. 

 The heat will cause the oxygen to separate from the mercury, and in a 

 short time the tube will be filled with the gas. Extinguish the flame 

 from a lighted splinter and thrust the glowing end into the tube ; what 

 happens ? The oxygen unites with something in the wood and causes it to 

 burn just as the match did. Compare your burnt splinter with the burnt 

 end of the match ; what resemblance do you notice between them ? 



EXPERIMENT 23. To SHOW THAT CARBON DIOXIDE is A PRODUCT OF 

 OXIDATION. Your experiment with the match showed that ignition 

 is accompanied by heat, and if active enough, by light, and also that 

 it left behind a solid substance in the form of charcoal. But how 

 about the part that united with the oxygen to produce these results? 



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