Ch 22: Living Organisms & Ecosystems

About This Chapter

Use these fun video lessons to review vertebrate characteristics, primate origins, animal body plans and the human musculoskeletal system. You'll also take another look at various ecosystems and the levels of ecology.

Living Organisms & Ecosystems - Chapter Summary

Get a quick refresher on the basic needs of living organisms before delving into lessons on the evolutionary history of vertebrates and the characteristics of primate groups, such as lemurs, tarsiers and anthropoids. You'll also rediscover components of the human muscular and skeletal systems.

The second half of the chapter can help you review the differences between environments, ecosystems, habitats and ecological niches. Lessons also cover the various levels of ecology and factors affecting an ecosystem's population density. Round out your study by re-examining the features used to define an organism's body plan. This chapter covers the following topics:

  • Living organisms' basic needs
  • Vertebrate characteristics and origins
  • Primate groups and human origin
  • The human muscular and skeletal systems
  • Ecosystems and habitats
  • Levels of ecology
  • Classifications of animal body plans

This chapter's illustrated videos feature an engaging instructional style that can help you commit key science terms and concepts to memory. Self-checking quizzes are also included to help you develop a solid understanding of what's being covered in the lessons. Plus, you can submit a question to one of our instructors if you need help at any point during your studies.

8 Lessons in Chapter 22: Living Organisms & Ecosystems
Test your knowledge with a 30-question chapter practice test
The Defining Characteristics of Living Organisms

1. The Defining Characteristics of Living Organisms

Organisms have traits, or characteristics, that determine they are alive and not simply appearing so. Explore the defining elements that all living things possess: cells, reproduction, growth & development, energy use, stimuli responses, regulation, and evolution.

Living Organisms: Basic Needs

2. Living Organisms: Basic Needs

There are basic needs that living organisms must satisfy to survive, that vary between diverse lifeforms. See the importance of sunlight, water, air, hospitable environment, and food to the survival of living species.

Vertebrates: Origin, Characteristics & Diversity

3. Vertebrates: Origin, Characteristics & Diversity

Vertebrates refer to all species of animals that have backbones. Explore the origin and evolution of vertebrates, learn about the non-vertebrate chordates and jawed vertebrates, and find out how the vertebrates tetrapods and amniotes first transitioned to land.

Primates and Human Origin

4. Primates and Human Origin

The origin of humans can be traced to primates due to similarities in anatomy. Learn about the characteristics of primates, the different types, and the characteristics of anthropoids.

Skeletal System and Muscular System

5. Skeletal System and Muscular System

The skeletal system provides a framework for muscles and tissues, protects the internal organs, and gives shape to the body, while the muscular system allows movement of the body, digestion, circulation, stability, and posture. Discover the major components of the skeletal system and the types of muscles in the muscular system.

Ecosystems, Habitats and Ecological Niches

6. Ecosystems, Habitats and Ecological Niches

Habitats are areas of the ecosystem where specific organisms live, while niches are the individual roles that organisms play within the ecosystem. Discover factors that affect an animal's niche and how population density impacts an ecosystem.

The Environment, Levels of Ecology and Ecosystems

7. The Environment, Levels of Ecology and Ecosystems

Ecology is the study of organisms and how they interact with the environment they live in. Explore ecology principles and the organismal, population, community, ecosystem, and biosphere levels of ecology.

Animal Body Plans: Classifications and Features

8. Animal Body Plans: Classifications and Features

The body plans of animals have different classifications and features that are affected by various factors. Learn about body plans, the types of body symmetry, body cavities and tissues, and locations of body structures.

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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