EXERCISE 31 



When the embryo has suitable conditions, it sprouts, or germinates. The small plant resulting is 

 known as a seedling. 



Problem. How do different seedlings break through the ground ? 



What to use. Various seeds beans, peas, corn, squash; sand, sawdust, or soil; a box or boxes 

 to hold sand ; water. 



What to do. Soak four varieties of seeds in water overnight ; plant a few of each kind in a box of 

 sand, sawdust, or soil ; keep well watered. 



Record. Make parallel drawings of several stages of growth of the seedlings showing behavior of 

 homologous (corresponding) parts. 



Questions. 1. What xhanges take place in the cotyledons as the seedlings develop? 



2. On the basis of the limited data obtained from the four species studied, fill in the above table. 



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