Why Do Fish Have Gills?

What Crafty Clover says in this video

Intro

Hey there, curious minds! I'm Crafty Clover! Let's discover something amazing. Why do fish have gills?

The Big Idea

Fish pull oxygen out of the water with thin gill tissues. We air-breathers use lungs instead. It is the same job with a different tool. That is why a fish can breathe even though it never comes up for air.

Water Enters the Mouth

Step one: water enters the mouth. A fish opens its mouth and takes in a mouthful of water. That water carries dissolved oxygen. Gills are packed with tiny blood vessels, so oxygen moves across easily.

Water Passes the Gills

Step two: water passes the gills. The water flows over many tiny gill plates. The plates are so thin that oxygen can slip right through.

Oxygen Moves Into Blood

Step three: oxygen moves into the blood. Blood in the gills grabs the oxygen and carries it around the body. The used water exits under the gill covers while the fish keeps swimming. Fast swimmers like some sharks need to keep moving so water keeps flowing over their gills.

A Closer Look

Let's take a closer look at a fish's head! The mouth takes in the water. The gill cover protects the gills. And the gill filaments are the thin plates that grab oxygen.

Quick Facts

Quick facts! If you catch a fish to look, use wet hands and return it fast. Out of water, gills collapse and stick together. A gill is like a net made of living paper. Still water holds less fresh oxygen than moving water.

Think Like a Scientist

Now, think like a scientist! Look at a picture of a fish with a grown-up. Find the gill cover behind its eye. Watch a fish in an aquarium and see its gill covers open and close. Why would still water be harder than moving water? Scientists watch closely and stay kind to animals. Happy exploring!

Outro

Gills are underwater lungs that work only in water! Crafty Clover can be found on Amazon Books, Google Bookstore, and Apple Books. Available for purchase or download! Bye for now!