Features of Fish: Jawless Fishes

The video explores the diversity of fish, highlighting that there are more fish species than all other vertebrates combined. It introduces ichthyologists, who have classified over 25,000 fish species. The focus then shifts to jawless fishes, such as lampreys and hagfishes, which are primitive vertebrates with cartilage skeletons. These fish lack jaws, paired fins, and scales. Lampreys are mostly parasitic, feeding on other fish, while hagfishes are scavengers. The video provides insights into the unique characteristics and feeding habits of these ancient fish groups.

What is the role of ichthyologists in the study of fish?

• They explore the depths of the ocean.

• They train fish to perform in aquariums.

• They classify and identify different species of fish.

• They study the migration patterns of birds.

Which of the following is a characteristic of jawless fishes?

• They have a characteristic head with jaws.

• They possess paired fins and scales.

• They have a skeleton made of cartilage.

• They have a skeleton made of bone.

How do lampreys obtain their food?

• By hunting small fish.

• By attaching to other fish and sucking their blood.

• By eating aquatic plants.

• By filtering plankton from the water.

What is the primary diet of hagfishes?

• Aquatic plants and algae.

• Insects and crustaceans.

• Dead fishes and large invertebrates.

• Live fish and small mammals.

Which of the following statements is true about lampreys?

• They are primarily herbivores.

• They are known for their vibrant colors.

• They are considered the most advanced vertebrates.

• Most of them are parasitic.