From the brains behind brains on, this is The Moment of Um.

Answering those questions that make you go.

Moment of Um um comes to you from APM Studios. I'm Molly Bloom.

Um. If you've been to the ocean before, do you remember the first time you took a dip in the wavy waters? Did you feel the sand beneath your feet? Did the waves lap against your shoulders? Did a seagull scream it's hello? And that's just the stuff you can see. So many incredible creatures swim beneath the

surface of the water. Fish, dolphins, sea lions, and one of the most exciting creatures of all time,

sharks. Sharks are amazing.

They have fantastic vision.

They've been around for 455 million years.

And if you flip them upside down, they go into a trance.

Maybe that's one of the reasons why I've heard that they never stop moving.

Hmm.

Why is that anyway?

Hi, my name's Wika, and I'm from Conca, California. My question is,

why do sharks die if they stop moving? That's a really good question. Um, hi everyone. My name is

Melissa Christina Marquez and I'm a shark scientist who studies where sharks are and why they're there.

So sharks have five to seven slits on the sides of their heads or underneath them,

depending if they're a shark or if they're a stingray. And those allow the animals to breathe.

Now, all of the sharks and the stingrays, they have this.

This is how they breathe.

They don't have lungs like you and I do.

So what happens is water will actually pass over the gills where there's tiny little blood vessels ready to extract oxygen from the salty water.

And then the carbon dioxide waste also passes from the shark's blood out of the body through the gills.

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