ORGANISMS ABOARD SHUTTLE

These are some of the organisms carried on Discovery: Roundworms: Microscopic worms that measure about 1 1/2 millimeters in length and normally dwell in soil or water. Each worm can produce 280 offspring in three days. Frog eggs and sperm: The eggs will be fertilized in orbit by the sperm, extracted from testes that were removed from frogs before flight. “Organ donation,” explained astronaut Roberta L. Bondar, a Canadian neurologist. Fruit flies: Genetic defects were noted in fly embryos flown on previous spaceflights, believed due to space radiation, and the females lived longer than males. Stick insects: An unusually high number of deformities also were noted in these larvae during previous shuttle missions. Slime mold: Small, simple organisms that live on decaying trees and in soil and move through contractions and dilations, poking along at about one-third of an inch an hour. Their movement will be studied in orbit. Fetal mouse leg bones: Calcium loss will be measured in an attempt to better understand bone demineralization suffered by astronauts in orbit.