Richard Burla, age 12, of Lethbridge, Alta., Canada, for his question:

WHAT ARE ANGIOSPERMS?

The term angiosperms belongs to botanists who study the plant world. To understand it, we must pair it with the term gymnosperm. Together they reveal two major classifications of plants. They also reveal a great deal about the age old history of the plant world, plus secrets about the many species that clothe our green earth.

All seed bearing plants are classed as either angiosperms or gymnosperms. About 55 million years ago, there were only the gymnosperms, meaning the naked seed plants. Their simple, smallish seeds had no pods, shells or tough outer coats to protect them. Most of the gymnosperms were evergreen conifers. They produced woody brown seeds under the scales of cones on the female trees. This worked well for countless ages  and some 500 or so splendid gymnosperms survived successfully in the modern plant world.

However, at last it became necessary to make some major improvements. After all, it takes a long time for a pine cone to produce a sprouting young tree. What's more, when a browsing animal bites off a cone bearing twig, a whole generation of seeds is lost. If the plant world was to spread and thrive as it should, obviously it needed quicker and safer methods of multiplication.

Eventually this led to the creation of the angiosperms, plants that produce covered seeds. Most experts suspect this fabulous project began when certain spore bearing leaves folded over and around to protect a fertilized plant seed. In time, this successful method branched out to produce the multitude of pods, shells and other hard coverings of the modern angiosperms.

The big problem was spreading pollen dust to reach and fertilize the seeds. However, this was solved by the creation of nature's dazzling display of flowers and tasty fruits. Flowers and fruits are angiosperm devices to attract insects and other animals to spread pollen from flower to flower and seeds to new locations.

Now 950,000 angiosperms produce flowers and seeds protected in hard cases. Flowers that depend on visiting insects to spread pollen, produce supplies of tasty nectar. Each species depends on certain insects to reach its nectar  and wears the favorite color plus the favorite perfume of its favorite insect. All these wondrous creations are part of the angiosperm story that began more than 50 million years ago.