Ch 25: Holt McDougal Biology Chapter 25: Vertebrate Diversity

About This Chapter

The Vertebrate Diversity chapter of this Holt McDougal Biology Companion Course helps students learn the essential lessons associated with vertebrate diversity. Each of these simple and fun video lessons is about five minutes long and is sequenced to align with the Vertebrate Diversity textbook chapter.

How It Works:

  • Identify the lessons in the Holt McDougal Vertebrate Diversity chapter with which you need help.
  • Find the corresponding video lessons with this companion course chapter.
  • Watch fun videos that cover the topics on traits of vertebrates you need to learn or review.
  • Complete the quizzes to test your understanding.
  • If you need additional help, rewatch the videos until you've mastered the material or submit a question for one of our instructors.

Students will learn:

  • Where vertebrates came from
  • Classes of jawless craniates
  • The development of jaws in vertebrate fish
  • Characteristics of bony fish
  • Tetrapods and their development of limbs
  • The function and characteristics of amphibians
  • Types of vertebrates that live on land

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8 Lessons in Chapter 25: Holt McDougal Biology Chapter 25: Vertebrate Diversity
Test your knowledge with a 30-question chapter practice test
Vertebrates: Origin, Characteristics & Diversity

1. Vertebrates: Origin, Characteristics & Diversity

Vertebrates are diverse and widespread across Earth, but this was not always the case. In this lesson you'll learn about the origins and evolution of these animals, as well as explore their vast diversity.

Jawless Craniates: Class Myxini & Class Petromyzontida

2. Jawless Craniates: Class Myxini & Class Petromyzontida

The word 'fish' brings specific images to mind. But before these fish existed, there were the jawless craniates. In this lesson you will identify two classes that fall into this category: the hagfishes and the lampreys.

Gills: Definition & Anatomy

3. Gills: Definition & Anatomy

Why can animals like fish and crabs breathe underwater but you can't? Aquatic organisms have a special organ called gills, which allows them to breathe oxygen in the water. Some gills are even adapted to allow animals to breathe on land!

Fishes and Sharks: Origins of Jaws in Vertebrates

4. Fishes and Sharks: Origins of Jaws in Vertebrates

While it may appear to be a minor feature, the hinged jaw led to major changes in the evolution of animals. In this lesson, you'll discover some of the earliest jawed animals, the sharks and fishes of the world.

Bony Fish: Characteristics, Anatomy & Types

5. Bony Fish: Characteristics, Anatomy & Types

Most of the world's fish are osteichthyes, meaning that they have bony skeletons. In this lesson, we will explore the definition, characteristics, anatomy, and some examples of bony fish.

Tetrapods: Development of Limbs in Vertebrates

6. Tetrapods: Development of Limbs in Vertebrates

Having four limbs allowed for an incredible amount of diversification in the animal kingdom. But where did those limbs come from, and what types of diversifications arose from animals moving onto land?

Amphibians: Traits, Types & Roles

7. Amphibians: Traits, Types & Roles

Amphibians. Does the word conjure up images of slimy frogs and salamanders? Or perhaps a case of warts after handling a toad? Amphibians are a fascinating group of animals that we don't see very often. Find out more in this lesson.

Land Vertebrates: Reptiles, Birds & Mammals

8. Land Vertebrates: Reptiles, Birds & Mammals

Things changed a lot when vertebrates left the water and moved to land. This lesson will compare reptiles, birds, and mammals to one another and explain why they look the way they do.

Chapter Practice Exam
Test your knowledge of this chapter with a 30 question practice chapter exam.
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Practice Final Exam
Test your knowledge of the entire course with a 50 question practice final exam.
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