Regeneration (Doctor Who)

Regeneration (Doctor Who) trivia questions

1. Which serial first depicted the Doctor changing body at the end of an adventure?
2. What visual effect marked the Doctor's 2005 change into a new face?
3. Which story revealed that Time Lords are usually limited to twelve body changes?
4. Whose body-change was triggered after absorbing the Time Vortex from Rose?
5. What unusual process split one incarnation into two in 'The Giggle'?
6. Which classic-era companion witnessed the very first on-screen body change?