Eli5 How do we hold our breath under water

Question

Whales have some flappy thing around their blow hole that they seal shut when under water only to open once above. I’m not aware of something like this for humans, yet the air does not gush out when we go underwater

In: 0

Answer 1

Humans can hold their breath underwater by closing their glottis, a part of the airway that connects the throat to the lungs. When you take a deep breath and hold it, the air fills up the lungs, and then the glottis closes, sealing off the airway so that air cannot escape. The air trapped in the lungs provides oxygen for the body until you can breathe again.

The epiglottis, which is a flap of cartilage at the base of the tongue, helps prevent water from entering the airway and lungs by closing off the windpipe when you swallow. This prevents food and liquids from entering the airway and lungs.