296 ] The Fascination of Flowers 



This tube forces its way down the style to reach an egg cell in the 

 ovule. As soon as the tube makes its connection with the egg cell, 

 the life-germ in the pollen slips through the tube to combine with 

 the life-germ in the egg cell. Thus the seed starts, developing on 

 food furnished by the plant and on warmth given by the sun. 



How THE SEED Is NOURISHED AND PROTECTED 



A fully developed seed is the embryo of a new plant, with 

 food stored around it in a form that can be used whenever new 

 growth begins. One of the amazing things about seeds is that 

 the stored food remains usable even though new growth does not 

 start for weeks, months, or even years! (This dormant period 

 varies, of course, with different kinds of seeds.) The embryo and 

 the food supply are protected by one or more layers of the ovule. 



Nuts and Tomatoes Are "Fruit": In some seeds, such as peas and 

 beans, the food supply is stored within certain parts of the embryo 

 itself. In other plants, corn and wheat for example, the food is 

 stored around, rather than in, the embryo. And still other plants 

 develop elaborate structures about their seeds. These structures 

 are called "fruit" apples and pears are familiar examples. When 

 a scientist speaks of a "fruit," he may be referring to the ripened 

 ovary of any kind of plant, be it the pod of a pea, a hard nut, 01 

 a juicy tomato. 



There are many opportunities for examining seeds for example, 

 when you are preparing dinner. To a hungry diner, peas, beans, 

 and corn are food; to a nature explorer, they are seeds! A child 

 is thrilled to see the first sprouting of the plant embryo after he 

 plants a few seeds in a glass with moist soil. If the seeds are placed 

 just inside the glass, they can be seen sprouting. 



How FLOWERS ATTRACT INSECTS 



When a child learns that pollen is transferred from one 

 plant to another by messenger insects, he may wonder what at- 

 tracts an insect to flowers is it their sweet scent or the color of 

 their petals? This is the kind of problem that scientists still ponder 

 and sometimes debate about. For many years it was a generally 



