Plant Study 



27 



FIG. 13. A practical seed- 

 tester for small seeds. 



EXERCISES 



1. Water in plants. Cut a white potato into pieces and observe 

 the water on the cut surface. How did the water get into the plant? 

 Place a small quantity of chopped hay in a test tube and heat slowly. 

 Why does moisture gather around the top of the tube ? Try the same 

 experiment with flour and starch. Where 



does the moisture come from? 



2. The seeds of plants. Soak a 

 few beans in water for about an hour. 

 Remove the seed-coat and find the germ 

 and the cotyledons. Make a seed-tester 

 by placing pieces of moist cloth between 

 two dinner plates, as shown in Fig. 13. 

 Place bean and corn seeds in the tester. 

 Keep the cloth moist and the tester in 

 a warm place for three or four days. 



Examine the seeds after they are sprouted and locate the radicle, 

 the plumule, and the cotyledons or cotyledon. After the roots of 

 the corn have become several inches long, examine them carefully and 

 compare with Fig. 14. 



3. Conditions necessary for germination. Arrange four seed- 

 testers like the one shown in Fig. 13 and place seeds in them. Label 

 them 1, 2, 3, and 4. Keep tester No. 1 moist and put it in a warm place. 



The seeds are warm, 

 moist, and supplied 

 with oxygen (air is pres- 

 ent between the pieces 

 of cloth) and if they are 

 alive they will sprout. 

 Do not moisten the 

 cloth in tester No. 2, 

 but put it in a warm 

 place. The seeds are 

 warm and supplied with 

 oxygen, but they are 

 not moist and will not 

 It 



FIG. 14. Parts of a sprouted maize kernel, 

 sprout. Keep tester No. 3 moist and place it in an ice-box. 



is supplied with moisture and oxygen, but not warmth ; the seeds 

 will not sprout. Keep the seeds in tester No. 4 covered with water, 

 and place the tester in a warm place. By keeping the seeds covered 

 with water you have practically cut off the oxygen supply and, as a 

 result, the seeds will not sprout. 



