Grade 5
Lesson 5
Marine Mammals - fish
Next
Previous
of
View all Lessons
Back to Lesson
Start
Quiz

Fish

Fish have a special line running on both sides of their body. They use this line to detect motion in the water. This alerts the fish to any predators or prey that may be around. Fish often swim together in groups called schools. When the group is attacked, some fish are eaten, but others escape

How do they breathe?

Fish have gills to get oxygen out of the water. They suck water in through their mouths and let it back out through their gills. In other words, fish need water to breathe.

G4 L1 P18

Lungfish

Most fish cannot live on dry land. One fish that can live on dry land is the lungfish. Its name says it all. This fish uses lungs to breathe!

How about the color?

Each fish has its own distinctive color. That color can change. For instance, when the fish wants to hide or when it wants to look pretty to another fish because it wants to mate.

What about the food?

Each type of fish goes after its own favorite meal. Some eat seaweed. Other fish prefer plankton, which are tiny shrimp and other animals that are so small you can hardly see them. Some eat both. Sharks are real predators. They hunt other fish.

What about the appearance?

Most fish have a smooth body, fins and a tail. Scales protect their soft bodies. These scales slide against each other so the fish can move. Some fish, such as de coffer fish have hard scales that cover their whole body. While snorkeling, you may see that they are only able to move their fins and mouth.

The Blowfish

The blowfish has scales shaped like spines. Do not get too close, because when it feels afraid, it can blow itself up and make its spines stand upright. That is not good for the blowfish or for yourself.

G4 L1 P20

Do fish parents care for their babies?

Do fish parents care for their babies?

Both right, Many species of fish lay eggs and do not stay around until these hatch, so they do not care for their young. However … some species do protect their young by carrying them around in their mouth. Once the danger is gone, they let the young out again.

Yes

Do fish parents care for their babies?

Both right, Many species of fish lay eggs and do not stay around until these hatch, so they do not care for their young. However … some species do protect their young by carrying them around in their mouth. Once the danger is gone, they let the young out again.

Yes

Did you know?

Sharks are fish. They are also known as cartilaginous fish. Their skeleton is not made of hard bone as that of other fish, but of cartilage, which is a light and flexible material like what we have in our nose and ears. Sharks have a fish shape and gills to breathe under water.

G4 L1 P21

Did you know that there are 250 species of shark and that only a few of those species are dangerous?

The dangerous ones are the great white shark, the blue shark and the hammerhead shark.

G4 L1 P22

Who is the largest fish?

The whale shark is the largest fish on earth. This species of shark is not dangerous. It is called whale shark because it eats plankton just like some whales do.

It can grow to more than 12 meters long
12

Did you know sharks have a very keen sense of smell?

They can smell one single drop of blood dissolved in over a million drops of water! They can also sense sounds from very far away. Sharks hunt mainly at night, when most animals are asleep and it is easier to find prey.

G4 L1 P23

Sharks

Sharks are very important to the sea. They are called the vacuum cleaners of the sea. They eat a lot of dead and sick fish. That way, they keep the sea healthy! Sharks have many rows of teeth. If a tooth breaks off from one of the front rows, a tooth from the row behind it moves forward and takes its place.

A shark could lose up to 30.000 teeth over its lifetime!
30000