Ch 16: Invertebrates

About This Chapter

Watch video lessons and learn about the different types of invertebrates and the characteristics that define them. Use the quizzes that follow each lesson to gauge your understanding of invertebrates.

Invertebrates - Chapter Summary and Learning Objectives

'Invertebrates' is basically another name for animals without spines. Since that includes a lot of sea creatures as well as insects and worms, invertebrates are a very large and important part of the animal population. This chapter looks at the different types of animal bodies that fall into the invertebrate category. You will be introduced to ocean invertebrates, worms, mollusks, echinoderms (such as starfish and sand dollars) and arthropods and insects. You'll learn about qualities they all share as well as features that set them apart from each other. By the end of this chapter you should be able to:

  • Define the broad characteristics of the animal kingdom
  • Give a definition and examples of the invertebrate category of animals
  • Describe the main features and distinctions of six different types of invertebrates
  • Explain the importance of these types of animals

Video Objective
Animal Body Plans: Classifications and Features Understand the main characteristics and different types of animal bodies.
Invertebrates: Definition & Examples Learn what separates invertebrates from other types of animals.
Ocean Invertebrates: Sponges & Cnidarians Describe key qualities of sponges and cnidarians (marine animals such as jellyfish).
Worms: Types & Features Learn the differences between flat, round and segmented worms.
Mollusks: Characteristics & Types Describe the features that define mollusks; learn some of the different types and understand what makes them important.
Echinoderms: Traits, Types & Roles Study echinoderms, such as sea urchins and starfish, and understand how they fit in the animal kingdom.
Arthropods: Definition, Characteristics & Types Define the features and the importance of crustaceans, centipedes and millipedes and arachnids.
Insects: Characteristics, Behavior & Extermination Explain the characteristics, food sources, reproduction and life cycles of insects; describe their importance and the efforts to control them.

7 Lessons in Chapter 16: Invertebrates
Test your knowledge with a 30-question chapter practice test
Animal Body Plans: Classifications and Features

1. Animal Body Plans: Classifications and Features

The Animal Kingdom is diverse and complex. How do we make sense of it all? Scientists use body plans to classify and organize the animals of Earth, making it much easier to differentiate between them.

Invertebrates: Definition & Examples

2. Invertebrates: Definition & Examples

From bees to lobsters and octopi to cockroaches, invertebrates are everywhere. This lesson introduces them as a major group within biology and discusses their relationship with the human race.

Ocean Invertebrates: Sponges & Cnidarians

3. Ocean Invertebrates: Sponges & Cnidarians

While some may call them simple, sponges and cnidarians have some amazing abilities. This lesson tells the story these ocean invertebrates, ranging from sponges to coral to jellyfish.

Worms: Types & Features

4. Worms: Types & Features

You may not know this, but worms are everywhere. Many are so tiny that we can't see them crawling all over the place like we can earthworms. In this lesson, we'll learn about some of the different types of worms around us.

Mollusks: Characteristics & Types

5. Mollusks: Characteristics & Types

Do you like to eat seafood, hunt for seashells, or learn about scary sea creatures? If so, then you'll want to learn about the different types of mollusks, which include the tasty bivalves, the cool-looking gastropods, and the weird cephalopods.

Echinoderms: Traits, Types & Roles

6. Echinoderms: Traits, Types & Roles

After watching this lesson, you'll be well on your way to being an echinoderm expert! For example, you'll learn that sea cucumbers help clean up the ocean floor and that starfish can grow back any arms that are broken or damaged.

Arthropods: Definition, Characteristics & Types

7. Arthropods: Definition, Characteristics & Types

Arthropods are the most abundant animals on the planet. They fly, jump, swim, and crawl over just about every inch of the world. Learn about common types of arthropods and the characteristics they have in common.

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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