Light micrograph (LM) of a salivary gland chromosome of Drosophila before puffing. Drosophila is a genus of flies, belonging to the family Drosophilidae, whose members are often called small fruit flies. Drosophila in particular, Drosophila melanogaster, has been heavily used as model organisms in genetics, cell biology, biochemistry, and developmental biology. The terms fruit fly and Drosophila are often used synonymously with D. melanogaster in modern biological literature. D. melanogaster is a popular experimental animal because it is easily cultured en masse out of the wild, has a short generation time, and mutant animals are readily obtainable. A chromosome is a DNA molecule with part or all of the genetic material (genome) of an organism. Magnification: x1200.