Why Do Many Sharks Keep Swimming?

What Crafty Clover says in this video

Intro

Hey there, curious minds! I'm Crafty Clover! Let's discover something amazing. Why do many sharks keep swimming?

The Big Idea

Sharks breathe with gills, and gills need fresh water flowing over them. Many open-water sharks swim with their mouths slightly open, so water streams in all the time. For those sharks, swimming is how they breathe!

Water Enters the Mouth

Step one: the shark swims forward, and water enters the mouth. As it moves ahead, water flows in with no pumping needed. This is called ram breathing.

Water Passes the Gills

Step two: water passes over the gills. Gills are thin, feathery folds filled with tiny blood vessels. Oxygen from the water slips into the blood, and the shark can breathe.

Used Water Exits

Step three: used water exits through the gill slits. Most sharks have five gill slits on each side. As long as the shark keeps moving, fresh water keeps flowing in.

A Closer Look

Let's take a closer look at how a shark breathes! Water enters through the mouth. It flows over the gills inside. And it leaves through the gill slits on the sides.

Quick Facts

Quick facts! Nurse sharks can rest on the bottom, and pump water over their gills. Great whites usually must keep moving to breathe. Open-water sharks are built for motion. And never pin or touch a wild shark.

Think Like a Scientist

Now, think like a scientist! Look up two kinds of sharks, like a nurse shark and a great white. Which one can rest on the bottom? Which one cruises in open water? Why would a shark that pumps water live near the bottom? And what does a cruiser need that a rester does not?

Outro

For many sharks, motion is breathing. Science is amazing! Crafty Clover can be found on Amazon Books, Google Bookstore, and Apple Books. Available for purchase or download! Bye for now!