In a north London hospital, scientists are growing noses, ears and blood vessels in the laboratory in a bold attempt to make body parts using stem cells. It is among several labs around the world, including in the U.S., that are working on the futuristic idea of growing custom-made organs in the lab. (Photo by Matt Dunham/AP Photo)

Visitors look at a plastinated gorilla on the opening day at the Body World Animals exhibition at the Cologne Zoo on April 15, 2011 in Cologne, Germany. The exhibition is by Gunther von Hagens, who uses a special process to preserve real bodies, whether animal or human, in order to display the inner organs, muscles and other physical elements. The exhibition will be open to the public until September 30.

A section of multi-vehicle accident on Interstate 75 is shown in Detroit, Thursday, January 31, 2013. Snow squalls and slippery roads led to a series of accidents that left at least three people dead and 20 injured on a mile-long stretch of southbound I-75. More than two dozen vehicles, including tractor-trailers, were involved in the pileups. (Photo by Paul Sancya/AP Photo)

An environmental activist adjusts his mask while taking part in “The Dead Sea Swim Challenge”, swimming from the Jordanian to Israeli shore, to draw attention to the ecological threats facing the Dead Sea, in Kibbutz Ein Gedi, Israel November 15, 2016. Swimmers from around the world plunged into the salty waters of the Dead Sea on Tuesday to attempt a seven-hour swim across the fabled lake in a bid to draw attention to its environmental degradation. Wearing protective masks and snorkels, 25 swimmers paddled through the muddy water to attempt the 9-mile (15-kilometer) swim from Jordan to Israel. (Photo by Nir Elias/Reuters)

A wounded protester is attended before being rushed to a vehicle following violence in Independence Square in Kiev February 20, 2014. Ukrainian protesters seized back Kiev's Independence Square in fresh clashes with riot police on Thursday that left several injured and possibly two demonstrators dead. (Photo by Konstantin Chernichkin/Reuters)

An Animal Liberation Victoria activist cries as she holds a dead animal at Federation Square on October 1, 2013 in Melbourne, Australia. Over 200 activists gathered with the bodies of deceased animals to publicly grieve their deaths. Animal Liberation Victoria is against the treatment of animals as “property” an promotes a vegan lifestyle. (Photo by Graham Denholm)

A cow, which escaped from a truck, attacks a farmer trying to catch it in Liangdun village of Nangang township, Anhui province December 15, 2013. The 700 kilogram (1,543 lb) cow attacked several farmers before being shot dead by policemen, local media reported. (Photo by Reuters/China Daily)