Kimberley Wilson and Dr Xand van Tulleken continue their journey around the human body. Read more
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Hair
Kimberley Wilson and Dr Xand van Tulleken continue their journey around the human body.
Fat
Kidneys
Kimberley Wilson and Dr Xand van Tulleken take a journey around the human body.
Sphincters
Knees
Dopamine
Tears
Kimberley and Xand find out there's much more to tears than meets the eye.
Ovaries
Wrist
Amygdala
