The Naked Scientist, Chris Smith strips science down to its bare essentials.How does grass break concrete?is one of the questions answered in this fascinating show. Like this podcast? Please help us by supporting the Naked Scientists

What stops water moving through a tiny hole, are ground up tablets safe to swallow, what are freckles, how fast can a human heart beat, what happens when a cataract is removed, where do fat flies come from and how does the moon influence the Earth? Join Dr Chris as he pits his wits against this week's round up of science questions from South Africa... Like this podcast? Please help us by supporting the Naked Scientists

This week Dr Chris discusses how volcanoes can cut global warming, the evidence for genes linked to race, whether ambidexterity is real, the cause of crop circles, news of a new vaccine for tuberculosis (TB) and the tale of a comet that turned into an asteroid... Like this podcast? Please help us by supporting the Naked Scientists

Are fat cells all made equal, why women glow while men perspire, the science of electromagnetic induction, what is emphysema, how are drug doses determined, is the Earth gaining weight and where does belly button fluff come from all go under the microscope in this week's Ask! the Naked Scientist from Talk Radio 702... Like this podcast? Please help us by supporting the Naked Scientists

Where does the waste from an aeroplane toilet go? And could you ever really get stuck to one when pressing the flush? Do we have bigger brains than 500 years ago? And why are planets spherical? We tackle all of these questions this week, as well as finding out that researchers have created an artificial nose even more sensitive than a dog's. Plus we'll discover why onions make your eyes water... Like this podcast? Please help us by supporting the Naked Scientists