In the study, muscle cells were injected into the cell-free "scaffolding" of a rat limb, which provided shape and structure onto which regenerated tissue could grow. Bernhard Jank, MD/Ott Laboratory, Massachusetts General Hospital Center for Regenerative Medicine hide caption

itoggle caption Bernhard Jank, MD/Ott Laboratory, Massachusetts General Hospital Center for Regenerative Medicine

Families harvest poppy bulbs in the Badakhshan province of Afghanistan. To collect the opium, they score the bulbs and let the milky substance ooze out. The dried residue contains about 10 percent morphine. David Guttenfelder/AP/National Geographic hide caption

itoggle caption David Guttenfelder/AP/National Geographic
Ikon Images/Corbis

A nurse in 1938 checks the amount of insulin in a needle. For many decades, the only insulin available to people with diabetes came from the pancreases of cattle or pigs. Insulin from animals is still available outside the U.S. — and cheaper than a recombinant DNA version. Bettmann/Corbis hide caption

itoggle caption Bettmann/Corbis

The research team used yeast chromosome No. 3 as the model for their biochemical stitchery. Pins and white diamonds in the illustration represent "designer changes" not found in the usual No. 3; yellow stretches represent deletions. Lucy Reading-Ikkanda hide caption

itoggle caption Lucy Reading-Ikkanda

This riboflavin-rich material can be used to print intricate, microscopic structures in three dimensions. Courtesy of North Carolina State University hide caption

itoggle caption Courtesy of North Carolina State University

A miniature ninja throwing star or a surgical device? The microgripper, shown here coming out of a catheter tube, is activated by body heat. The sharp appendages fold up when the device warms up. Evin Gultepe, Gracias Lab, Johns Hopkins University. hide caption

itoggle caption Evin Gultepe, Gracias Lab, Johns Hopkins University.

Medical geneticist Dr. Harry Ostrer (center) talks to the press outside the U.S. Supreme Court on Monday. The court heard oral arguments on the highly charged question of whether human genes can be patented. Mladen Antonov/AFP/Getty Images hide caption

itoggle caption Mladen Antonov/AFP/Getty Images