Why do I want to eat chalk?

Why do I bruise more easily now I'm older? Why do some wind turbines spin in reverse? Are UV sunbeds worse for young skin? Ozone therapy, or quackery? Why do I want to eat...

04 May 2012

Presented by Chris Smith.

CHALK-BOARD

Credit:

CC0, Masae, via Wikipedia

Play Download

Why do I bruise more easily now I'm older? Why do some wind turbines spin in reverse? Are UV sunbeds worse for young skin? Ozone therapy, or quackery? Why do I want to eat chalk? Is blood the same in all animals? And alongside the answers to the best science questions 702 listeners have to offer, Dr Chris also reveals new radio-controlled cells...