prize for physiology or medicine 2009 jointly to -- >> elizabeth blackburn, carol greider, and jack chesterll worked in the united states. and they cracked one of the biggest mysteries in size. in order to grow and fill, humans depend on cells dividing and replicating. but how did this work exactly? this is the answer. at the very tips of our chromosomes, there can be teleomeres. they're like shoelaces that keep them from unraveling. without these, we just would not work. the research could have massive implications for all of us. these shoelace and mcgovern the aging process. when they do not function properly, they also can be responsible for the production of cancer cells. research is already underway appeare. >> i was lucky to reach all of them. they were a bit sleepy when they got the call, but they were very happy. >> awaiting them there will be a check for $1.4 million and the right to call themselves nobel laureates. >> please stay with us. bbc world news. taking the law into their own hands, controversy is building over italy's new breed of citizen police. first, an organization ha