Salamanders' immune systems are key to their remarkable ability to regrow limbs, and could also underpin their ability to regenerate spinal cords, brain tissue and even parts of their hearts, scientists have found.
It starts with a tickle in your throat that becomes a cough. Your muscles begin to ache, you grow irritable, and you lose your appetite. It's official: you've got the flu. It's logical to assume that this miserable medley of symptoms is the result of the infection coursing through your body - but is that really the case? Marco A. Sotomayor explains what's actually making you feel sick.
Starfish can regrow lost arms, and salamanders can sprout new limbs. So why can't we? Sci Show explains the science of regeneration, and explores the limitations the humans face -- and are trying to go beyond.
Hank tells us about the team of deadly ninja assassins that is tasked with protecting our bodies from all the bad guys that want to kill us - also known as our immune system.