This week we hear how lasers might replace X-rays as a way to see inside the body, we delve into the genetic code of the extinct woolly mammoth and hear about a government competition to exploit the power of the web to help people to find public toilets and post boxes. We also tackle your science questions including finding out why mosquiotoes don't transmit diseases like dirty needles, how animals cut their umbilical cords, whether it's better to drink red wine or grape juice and why cold tea tastes strange! Plus, Dave creates a ghostly one-way window effect in Kitchen science.