Ch 16: Invertebrates: Help and Review

About This Chapter

The Invertebrates chapter of this Middle School Life Science Help and Review course is the simplest way to understand animals without a background. This chapter uses simple and fun videos that are about five minutes long, plus lesson quizzes and a chapter exam to ensure students learn the essentials of invertebrates.

Who's it for?

Anyone who needs help understanding middle school life science material will benefit from taking this course. You will be able to grasp the subject matter faster, retain critical knowledge longer and earn better grades. You're in the right place if you:

  • Have fallen behind in understanding animal body plans or invertebrates.
  • Need an efficient way to learn about invertebrates.
  • Learn best with engaging auditory and visual tools.
  • Struggle with learning disabilities or learning differences, including autism and ADHD.
  • Experience difficulty understanding your teachers.
  • Missed class time and need to catch up.
  • Can't access extra science learning resources at school.

How it works:

  • Start at the beginning, or identify the topics that you need help with.
  • Watch and learn from fun videos, reviewing as needed.
  • Refer to the video transcripts to reinforce your learning.
  • Test your understanding of each lesson with short quizzes.
  • Submit questions to one of our instructors for personalized support if you need extra help.
  • Verify you're ready by completing the Invertebrates chapter exam.

Why it works:

  • Study Efficiently: Skip what you know, review what you don't.
  • Retain What You Learn: Engaging animations and real-life examples make topics easy to grasp.
  • Be Ready on Test Day: Use the Invertebrates chapter exam to be prepared.
  • Get Extra Support: Ask our subject-matter experts any relevant question. They're here to help!
  • Study With Flexibility: Watch videos on any web-ready device.

Students will review:

In this chapter, you'll learn the answers to questions including:

  • How are animal body plans classified?
  • What are the primary features found in different types of worms?
  • Why are mollusks important to the study of invertebrates?
  • What are the different types of arthropods?
  • How do insects develop, obtain food and reproduce?

18 Lessons in Chapter 16: Invertebrates: Help and Review
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.

Echinoderm Reproduction & Larvae

8. Echinoderm Reproduction & Larvae

Echinoderms are a strictly marine group of invertebrates that include starfish, sea urchins, and sand dollars. Learn about both the asexual and sexual reproduction of different echinoderms.

Echinodermata Circulatory System

9. Echinodermata Circulatory System

Learn about the circulatory system of members of the phylum Echinodermata. They have an unusual circulatory system when compared to humans and mammals - an open system with no true heart!

Echinodermata Digestive System

10. Echinodermata Digestive System

Learn about the digestive system of the phylum Echinodermata - invertebrates that include starfish, sea urchins, and sand dollars. They have simple digestive systems when compared to other animals. Learn about what they eat and how they digest it.

Echinodermata Nervous System

11. Echinodermata Nervous System

Learn about the nervous system of the members of the phylum Echinodermata. Members of this invertebrate marine phylum include starfish, sea urchins and sand dollars. Though they lack brains, echinoderms do have a nervous system and sensory organs.

Examples of Symmetry in Phylum Platyhelminthes

12. Examples of Symmetry in Phylum Platyhelminthes

Almost all creatures in the animal kingdom show some kind of symmetry. Read on to learn what the Platyhelminthes are and what kind of symmetry they exhibit.

Phylum Echinodermata: Definition, Characteristics & Examples

13. Phylum Echinodermata: Definition, Characteristics & Examples

Learn about echinoderms, which include starfish and sand dollars, in this lesson. We'll discuss what an echinoderm is, examine what their defining features are, and go over some examples of the five classes that make up the phylum Echinodermata.

Phylum Mollusca: Digestive, Nervous & Circulatory Systems

14. Phylum Mollusca: Digestive, Nervous & Circulatory Systems

Learn about the animal phylum Mollusca and its most important body systems. Mollusca includes a wide range of common invertebrate species that can inhabit land, freshwater, and saltwater environments, making them an extremely diverse group of organisms.

Which Mollusks Have Shells?

15. Which Mollusks Have Shells?

Mollusks are a diverse set of creatures that have been around thousands of years. Read this lesson to learn what types of mollusks have shells, the different subcategorizations of shell-carrying mollusks, and how their shells are made.

Cnidarian Life Cycle

16. Cnidarian Life Cycle

Cnidarians are a group of aquatic organisms that undergo a two-part life cycle. This lesson describes the Cnidarians, their characteristics, and the detailed (yet fascinating) reproductive process they employ.

Cnidaria Nervous System

17. Cnidaria Nervous System

In this lesson, we'll take a look at the simple and elegant nervous system of the Phylum Cnidaria. Cnidarians include hydras, sea jellies or jellyfish, sea anemones, corals, and box jellies. Their nervous system allows them to sense their environment, move through the water, and capture prey.

Gastropod: Definition, Characteristics & Examples

18. Gastropod: Definition, Characteristics & Examples

The animal class Gastropoda includes a range of aquatic and land-dwelling animals. Learn about what makes a gastropod a gastropod, and which animals are members of the class.

Chapter Practice Exam
Test your knowledge of this chapter with a 30 question practice chapter exam.
Not Taken
Practice Final Exam
Test your knowledge of the entire course with a 50 question practice final exam.
Not Taken

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