Sperm Can't Turn Left, Or Don't Want To
Sperm Up Close Joyce Harper, UCL, Wellcome Images A new imaging technique allows researchers to follow the agile, elusive male reproductive cell. Sperm are small, but they're quick-an individual sperm can wiggle through a space 25 times the length of its body in a single second. (For comparison, a human would have to run 540,000 miles per hour to achieve the same relative speed.) The sperm's combination of tininess and agility makes them almost impossible to track, since researchers have to zoom way in with their microscopes to see the frenetic flagellates at all (think of following a fast-flying bird through binoculars, except moreso). That's where Aydogan Ozcan (one of PopSci's own Brilliant Ten!) comes in: the UCLA engineer has developed a method to record the motion of individual sperm cells using a "lens free" imaging platform. To track the sperm, Ozcan and his team positioned two LEDs-one red, one...