Chris and Xand dig deeper into the role of testosterone with Dr Channa Jayasena, expert in reproductive endocrinology from Imperial College London.

They discuss how testosterone interacts with other hormones, particularly oestrogen and the different roles these hormones play when it comes to male and female biology. They also explore the populism of testosterone.

If you’d like to share your thoughts on this, or any other topic in the series, you can email at whatsupdocs@bbc.co.uk or Whatsapp on 08000 665 123.

Presenters: Drs Chris and Xand van Tulleken Guest: Dr Channa Jayasena, Imperial College London Producer: Jo Rowntree Executive Producer: Rami Tzabar Editor: Kirsten Lass Assistant Producer: Maia Miller-Lewis Researchers: Lisa Lipman Tech Lead: Reuben Huxtable Social Media: Leon Gower Digital Lead: Richard Berry Composer: Phoebe McFarlane Sound Design: Melvin Rickarby

At the BBC: Commissioning Editor: Rhian Roberts Assistant Commissioner: Greg Smith

A Loftus Media production for BBC Radio 4.

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