Barbara Erban, Age 1.1, Of North Andover, Mass., for her question:

Why are most plants green?

In a few weeks, the fall season will be with us and the leafy plant world will don colors that rival the rainbow.. The forested mountains and handsome hills around boston always dazzle New Englanders with their autumn displays. Nevertheless, the basic color of the plant world is green.
There is not one basic color in the animal kingdom. Its creatures wear assorted colors ranging from the drab fur of the mouse to the vivid plumage of the cardinal, from the shaggy black coat of the bear to the snowy plumage of the swan. But nature selected one basic color for the plant kingdom. Almost all plants wear some shade of green. The name of this basic green paint is chlorophyll and nature daubs it with a lavish brush through fields and forests, gardens and grassy meadows.
The colors of the animals often match their backgrounds and help to hide them from foes and victims. But the basic green of the plant world plays a far more vital role than this. During the daylight hours, chlorophyll runs a busy chemical factory. From such simple chemicals as gases and water, it produces the staple groceries that plants need to bud and grow, to thrive and multiply all plants are nourished by inorganic or non living chemicals, and most of them need chlorophyll to manufacture their basic food. There are several types of Chlorophyll, all made from molecules. Each molecule is an interlocking army of atoms.  Most of the atoms are carbon and hydrogen, a few are nitrogen or oxygen, and each  Chlorophyll molecule has one atom of magnesium.
Green chlorophyll is a grainy substance made of small bodies called chloroplasts. It takes about one billion chlorophyll m01ecuies to make one tiny chloroplast. It takes about 300 million chloroplasts to color a square inch on the surface of a leaf. And this soothing green paint is actually a busy chemical producing the groceries to support the life processes in the growing plant.
Mushrooms and other fungi are sickly looking plants of pasty white. They have no green chlorophyll and must depend upon the foods produced by green plants. They must grow in loamy soil rich in decaying plant material. Most plants are green because they need chlorophyll to manufacture their food  and this miraculous chemical is green.
The foliage of the plant world teams with other chemicals somewhat similar to chlorophyll. They mingle their red, purple and ye11ow tones with chlorophyll and modify its leafy green. The yellow chemicals teem in sunflowers and goldenrod, lemons and carrots. The purple chemical tints the plums and barberries. The red tones tint the ripe cherries and after summer, when the busy chlorophyll has done its work and broken apart, they are there to splash the marsh map1e with vivid scarlet.