Arnie Hochman, age 11, of ,Bessemer, Ala., for his question:

IS THE EUGLENA A PLANT OR AN ANIMAL?

Euglena is a group of microscopic organisms that scientists classify both as plants and animals. There are about 150 different kinds.

It would take up to 1,000 euglenas lined up next to one another to measure one inch, so you can see the organisms are extremely small. Most contain chlorophyll which gives them a green coloring.

Like higher plant species, euglenas get energy from sunlight. Like many simple animals, they use a whiplike appendage called a "flagellum" that sticks out from the body and helps them to move about.

Euglenas live in fresh water and are especially common in warm seasons when they may form a green scum on the surfaces of small ponds or drainage ditches.