Raw Science 5: Humidification & Dihydrogen Oxide

Basic Science Clinic by Steve Morgan & Sophie Connolly  "…water is the driving force of all nature….without it, nothing retains its form." Leonardo Da Vinci Welcome to Basic Science Clinic Raw Science episode 5. Let's get down to business and accompany oxygen on its relentless tumble from nasopharynx to mitochondria down the partial pressure staircase that explains how 160 mmHg of inspired oxygen partial pressure becomes 20 mmHg in the inner mitochondrial matrix. In this pod we will examine step one of this cascade and the science of the humidification of dry, inspired atmospheric gas, whilst paying deference to dihydrogen oxide. Water is pretty amazing stuff. It is the solvent of life characterized by anomalous idiosyncrasies without which biology wouldn't even be a thing.  It is the only substance found concurrently in 3 phases on Earth's surface and is a byproduct of the outpouring of stellar gas and dust produced when a star is born. NASA recently discovered a water vapour cloud surrounding a quasar 12 billion light years away, a celestial snapshot capturing the antiquity of water in the universe.   What to expect: What makes water so special? What is water's role in the first step of the oxygen cascade? What is the difference between a gas and a vapour? How do you define humidity?   Raw Science Factoids The length of the side of a cube that could hold all of Earth's water is 1150 km, containing 1.5 billion km3 or 800 trillion Olympic swimming pools. Everywhere there is liquid water on Earth there is life inspite of temperatures of 100s of degrees or searing acidity. All of Earth's water likely arrived on carbonaceous meteorites that can be up to 20% water as ice, between 4.5-3.8 billion years ago during the late heavy bombardment. Thanks for listening. For feedback, corrections and suggestions find us on twitter @falconzao and @sophmcon or post on ICN. Next up we'll scrutinize respiratory gas flow.