Operation Ouch! - Series 6: 8. Marvellous Valves - Signed

Name: Operation Ouch! - Series 6: 8. Marvellous Valves - Signed
Description: Dr Chris and Dr Xand find out why blood rushes to your head when you are upside down but doesn't rush to your feet when you're standing up!

Dr Chris and Dr Xand find out why blood rushes to your head when you are upside down but doesn't rush to your feet when you're standing up!